Alternatives to Berlin Hauptbahnhof

The main-line railway network in Berlin has insufficient capacity, for frequent long-distance and inter-regional services. That is not clearly visible at present, because services in Germany are far from ‘frequent’.

Berlin Hauptbahnhof: image by Dontworry under CC3.0 licence…

 
Even on the flagship ICE network, most lines have less than one train per hour. In fact, no ICE line has a 60-minute frequency over its entire length (2014). The high-speed sections (Schnellfahrstrecke) typically carry several ICE services, so combined frequencies are higher. At the edge of the network, however, frequencies are low, perhaps only a few trains per day. On the remaining ‘classic’ Intercity network, no single line has a 60-minute frequency. For comparison: the planned high-speed line north from London would carry 17 trains per hour. The Netherlands has high Intercity frequencies, with ten domestic Intercity trains per hour, through Schiphol Airport station. A 10-minute Intercity service is planned for several main routes.

Service frequencies are in any case lower in eastern Germany, than in the more densely-populated west. Around Berlin, the Regional-Express services usually run at a 60-minute interval: the remaining regional trains (Regionalbahn) usually less than that.

So there are fewer trains into Berlin, than you would expect given its population (4 million), its status as capital of Germany, and its geographic location. There are historical reasons: the post-war annexations brought the Polish border to 80 km from from Berlin, cutting eastern long-distance traffic to almost zero. The division of Germany did the same with traffic to the industrial west. Post-war refugee flows, and eastern population decline, concentrated population in western Germany. Nevertheless, the main factor is the central place of the car in German society, and the resulting lack of political commitment to rail transport.

And so the new main station in Berlin, Berlin Hauptbahnhof, is currently sufficient for all traffic. Not because it is too big, but because there are not enough trains. In fact, the station is smaller than its combined predecessors – Berlin once had 11 terminal stations. Most were destroyed by bombing in the Second World War

Ruin of the Anhalter Bahnhof, Bundesarchiv image…

 
A modern station with through platforms can process more traffic, than a 19th-century terminal station. However, even if the platform capacity is adequate, the rest of the infrastructure is not. Some of the lines into Berlin have not been touched since the Berlin Wall was built in 1961, or even since 1945. That too illustrates the low priority of rail transport in Germany. The new central station looks impressive: politicians find that more important, than whether trains can reach it.

Capacity issues in Berlin: north side

Typical capacity problems in Berlin were mentioned here earlier, in the proposal for an upgraded Prignitz line, Berlin – Neuruppin – Wittenberge, the old Kremmener Bahn. Historically, there were two main lines into central Berlin on the north side – Nordbahn and Stettiner Bahn. The Kremmener Bahn and the local line Heidekrautbahn branched from the Nordbahn, about 5 km from this station – so there were four northern routes into Berlin.

Trains used the terminal station Nordbahnhof. It was built by the Stettiner Bahn, and originally called the Stettiner Bahnhof, until 1950. The name Nordbahnhof was originally used for a separate freight station. In 1903, the approach tracks were re-aligned, to allow interchange with the ring line, Ringbahn. All tracks now ran parallel through the station at Gesundbrunnen, even though that meant two right-angled turns.

Gesundbrunnen in 1906: public domain, via Wikimedia…

When Berlin was divided, this route was disrupted. In combination with the new Hauptbahnhof project, Gesundbrunnen station was reconstructed, and services restored by 2005. The northern Ringbahn has become an approach line for Berlin Hauptbahnhof (Pilzkonzept).

The current arrangement is similar to the 1903 layout, with Berlin Hauptbahnhof replacing the function of the old Nordbahnhof. Trains make a right-angle turn, pass through Gesundbrunnen, make another right-angle turn, and approach the main station from the north. However, the old Nordbahnhof had separate approach tracks, and they have disappeared.

Gesundbrunnen has ten platform tracks, but west of the station there are only two tracks, for all trains except the S-Bahn. The S-Bahn itself has four exit tracks on the western side, for north-south and Ringbahn traffic. However, when the planned second north-south line is built (S21), it will also share the S-Bahn tracks eastward, and the platform tracks at Wedding station – inevitably reducing capacity.

Gesundbrunnen: 10 tracks in, 6 tracks out…

 
For optimal capacity, there should therefore be eight tracks between Gesundbrunnen and Wedding, instead of four. That is the only way to separate east-west and north-south trains passing through Gesundbrunnen.

At present the issue is academic, because there are so few trains. In fact, there are no trains at all over the old Nordbahn – because the mainline tracks have still not been reinstated. There are no regional trains from the Kremmener Bahn, because there are no tracks for them either. And there are no regional trains from the Heidekrautbahn, because its tracks inside Berlin have not been reinstated either.

East of Gesundbrunnen, the Ringbahn is well connected to the Görlitz line, via new platforms at Ostkreuz. When the reconstruction of Ostkreuz station is complete, that would be a useful route toward the new Berlin Brandenburg Airport (BER, formerly BBI), although no such service is planned.

The connection to the other eastern radial lines, toward Lichtenberg and Karlshorst, is inadequate. There are flat junctions at both ends, and with the Lichtenberg – Ostkreuz curve, and there are single-track bottlenecks. At present that is also a theoretical issue: there are no regular train services anyway.

Spandau line capacity and design

The same issues recur on other approaches to Berlin: tracks abandoned for 50 or 60 years, insufficient capacity, and design faults.

The north-western approach to Berlin Hauptbahnhof also uses the Ringbahn. The main lines from Hannover and Hamburg converge at Spandau: trains continue east along the Ringbahn, and then make a right-angle turn south into Hauptbahnhof. Again this replicates the historical layout – the new station has approximately the same location, as the old Lehrter Bahnhof and Hamburger Bahnhof.

The tunnel into Berlin Hauptbahnhof: middle tracks from Gesundbrunnen, side tracks from Spandau, image by Falk2 under CC3.0 licence…

 
Again there is a grade-separated junction, so that some trains can go to Hauptbahnhof, while others continue toward Gesundbrunnen. But again, it can not operate to full capacity, because the line from Spandau does not have four tracks over its entire length. There are six tracks into Spandau, but only four tracks onward, over the Havel bridge, and two of them diverge toward Charlottenburg.

On the Ringbahn tracks toward Hauptbahnhof, there is one intermediate station, Jungfernheide. Regional trains stop here, but there are no through tracks for fast trains, another design error. (There are four tracks available at Jungfernheide, but two are not connected to the Spandau line). The connections to the western section of the Ringbahn are also inadequate.

And again, the new north-south S-Bahn has its own exit tunnel, but it connects to the existing platforms at Westhafen station. There will be four tracks into this station, but only two tracks out. That will be a problem for any extension of the S-Bahn west to Spandau.

The northern Ringbahn simply does not have the capacity for the function assigned to it in the Pilzkonzept. The same is true for the east-west line through Berlin Hauptbahnhof, the Stadtbahn.

Capacity on the Stadtbahn

The Berliner Stadtbahn is an east-west line, on brick viaduct through the historic centre of Berlin. It was opened in 1882 to connect to six radial lines. It also passed the old Lehrter Bahnhof and Hamburger Bahnhof, offering additional connections. The line was built with four tracks, with local and long-distance traffic separated from the start. The local tracks were electrified in the 1920’s, the first ‘S-Bahn’ line.

A four-track viaduct through a city centre is inevitably constricted by surrounding buildings. The alignment has many curves and S-bends. Space for the stations was also limited. Such a line would not be built today.

Stadtbahn at Hackescher Markt: image by H0tte, public domain…

 
The line is clearly obsolete. When Berlin Hauptbahnhof was built, the logical option was to replace it by an east-west tunnel – but there was no money for that. However, maintaining and using a low-quality line also costs money – probably more in the long run. The curved alignment itself restricts speed, and increases the risk of delays. With only two tracks, there is no separation of regional and long-distance trains, and at Alexanderplatz they share one island platform.

At the western end, the line is accessible from the Spandau and Potsdam lines, with a grade-separated junction at Westkreuz. These lines were not left to rot, because they were the main routes into West Berlin, when Germany was divided.

At the eastern end, at Ostbahnhof, the Stadtbahn is connected to five platform tracks. However, they are only directly connected to the Niederschlesisch-Märkische Eisenbahn, the current main line to Poland. The other connections were abandoned during the division of Berlin, when east-west train traffic was minimal. The current reconstruction of Ostkreuz station allows for only a single-track connection to Lichtenberg, on the former Ostbahn main line. (The Görlitz line is accessible via the outer ring line BAR).

South of Hauptbahnhof

The main lines from Magdeburg, Halle and Dresden originally had three terminal stations: Potsdamer Bahnhof, Anhalter Bahnhof, Dresdener Bahnhof. They were built beside each other, at the southern edge of the city centre. In principle, the four-track tunnel into Berlin Hauptbahnhof should allow it to replace their function. However, the new Hauptbahnhof is still not fully connected, to the three historic lines into Berlin.

Only the Anhalter Bahn toward Halle has been entirely restored. To reach the Dresden line, trains use the Anhalter Bahn, and then the outer ring line BAR. Restoration of main-line tracks, on the Dresden line inside Berlin, has only just entered the public consultation phase.

Reconstruction of the Potsdam main line (Stammbahn) has been under discussion for 20 years, without any progress. It is not clear if the design of the north-south mainline tunnel allows for a grade-separated junction. A flat junction with the Stammbahn would severely reduce capacity here. The regional train station at Potsdamer Platz already reduces capacity on the north-south tunnel, since it has no through tracks.

More tracks on the radial lines

There are currently 11 main lines and 3 regional lines into Berlin. One regional line (Neukölln – Mittenwalder Eisenbahn) has been entirely abandoned. Some of the lines are duplicate routes, and it is also possible to create new link lines between them, allowing more effective distribution of services. Nevertheless, capacity on the radial lines is generally insufficient for high service frequency.

Only five of the main lines have a parallel S-Bahn line, to beyond the outer ring line (BAR). Only the Hannover main line has four tracks, as it crosses the BAR. If other S-Bahn lines were extended, then trains could run non-stop for about 25 km out of Berlin. If all trains can run at line speed – probably about 150 km/h – then capacity would be maximised. Further from Berlin, additional tracks will be needed on some lines, otherwise regional and freight trains will obstruct high-speed services.

Again these capacity problems are invisible at present. If there is only one ICE every two hours, and one regional train per hour, then two tracks is enough. Upgrading of several radial lines was proposed here earlier:

• conversion of the former Preussische Ostbahn out of Berlin, to a high-speed line Berlin – Riga. That would require new separate fast tracks, from Berlin Ostbahnhof to Lichtenberg, and probably four tracks east of Strausberg.
• new high-speed sections between Berlin and Rostock
• new high-speed sections between Berlin and Hamburg
• extra tracks on the Hannover line and connection to Nauen

That is an indication of what might be done, on the other radial lines. Obviously, these proposals assume a much greater frequency of services, of all types. That would certainly exceed the combined east-west and north-south capacity, at Berlin Hauptbahnhof.

Adding capacity inside Berlin

One option to increase east-west capacity has been proposed here already – a new high-speed route at the southern edge of Berlin. It would consist of a new line from Potsdam to the new airport, and a connecting high-speed line to Frankfurt (Oder).

 

 
Inside the built-up area of Berlin, the first logical option is to upgrade the northern Ringbahn. If all the bottlenecks were removed, that would create an east-west route with its own tracks, from Spandau to Ostkreuz via Gesundbrunnen. Upgrading would be controversial, because it would require demolition of housing in Gesundbrunnen.

The improved northern Ringbahn could be used for regional and interregional services. All services would be by electric trains, which means that some lines outside Berlin must be electrified. The most logical pattern of services is from north-west (Spandau) to south-east (Frankfurt and Cottbus lines). To improve connections, a new link could be built between those lines. It could cross the Spree towards Karlshorst, or run between Schöneweide and Köpenick stations, partly parallel to the S-Bahn. With this new link, all trains can run through Ostkreuz, before turning south-east.

 
The western and southern Ringbahn can also be upgraded for regional trains. However, they do not offer the same logical and direct routes, as the Northern Ringbahn. The alignment is also sharply curved in places. At present, it carries no passenger trains. The new Südkreuz station, which is the main interchange on the southern Ringbahn, has no platforms for regional trains.

Südkreuz…

 
Regional trains from Spandau can reach the southern Ringbahn via the western Ringbahn. There would be no intermediate stations until Westkreuz, with new regional platforms alongside the S-Bahn station (shown in orange). To improve connections, regional trains from Potsdam via Wannsee should also stop at Westkreuz. They would have their own separate platforms (shown in yellow), replacing Charlottenburg regional station.

Click to enlarge: Westkreuz…

 
It is not logical for Potsdam trains to turn south-east onto the Ringbahn, since a restored Potsdamer Stammbahn offers an alternative route. They might use the western Ringbahn toward Gesundbrunnen: there is a connecting curve, but with little space for platforms (shown in blue). Equally, it is not logical to connect the Ruhleben link line to the southern Ringbahn, since the western Ringbahn offers an alternative route.

On the southern Ringbahn, regional trains from Westkreuz would stop at new platforms at Südkreuz and Hermannstrasse. The only good connection east of Hermannstrasse is to the Görlitz line, and therefore potentially to the new airport. However, that route is well served by the planned extension of S-Bahn line S45.

Planned connections to BER airport: map by Robert Aehnelt under CC3.0 licence…

 
The eastern section of the Ringbahn, toward Ostkreuz, is of little use to regional trains. However, the utility of the southern Ringbahn can also be improved by a Köpenick link, which would allow regional trains to run from Südkreuz and Hermannstrasse to Erkner.

New tunnels

More radical options are a second north-south tunnel, a new east-west tunnel, and a second main station.

There are several possible options for a new north-south tunnel. An alignment between Bornholmer Strasse and Ostkreuz would maximise new approaches to central Berlin, and compensate for the design errors around Gesundbrunnen. It would connect the two main northern lines (Nordbahn and Stettiner Bahn), to the main eastern lines (Ostbahn and Niederschlesisch-Märkische Eisenbahn). An extension under the Spree could also connect it to the Görlitzer Bahn.

 
The tunnel would be about 8 km long. From the northern portal at Bornholmer Strasse, it would follow the alignment of the old Nordbahn freight yard – still free of buildings, because the Berlin Wall followed the railway here. At the southern end, the tunnel would climb alongside the existing railway toward Ostkreuz. The long approaches are necessary, because only a deep tunnel can pass under central Berlin. The tunnel would allow trains to pass quickly through Berlin, but also serve a city centre station. The only logical station site is at Alexanderplatz, at the eastern edge of central berlin. To avoid the U-Bahn and deep foundations, the station would probably be under the Alexanderstrasse.

A new east-west tunnel to replace the Stadtbahn, would be at least 12 km long, and possibly 16 km. Again it could only run in deep tunnel under central Berlin, and requires long approaches. The east portal would probably be at Ostkreuz, or possibly at the old Görlitzer Bahnhof. The west portal would be at Westkreuz, or even at Ruhleben – or both. The shortest alignments would run south of the city centre, but that makes interchange with the north-south main line difficult. The optimal location for an interchange station is at Potsdamer Platz station, but it seems impossible to build a new east-west station, under all the existing tunnels here.

The tunnels at Potsdamer Platz: map by Zuzien1 under CC3.0 licence…

 
An east-west tunnel south of the city centre was planned, before and during the Second World War. It is seen as part of Hitler’s plans for a grandiose capital city, Welthauptstadt Germania, but the proposed alignment was quite modest. About 4 km long, it would have linked the Görlitzer Bahnhof to the Anhalter Bahnhof, with four intermediate stations. (Despite their megalomania, Hitler and Speer did not plan a main-line rail tunnel under Berlin, nor a single central station).

A new east-west tunnel is a precondition for a second main station. Given the difficulty of a large new underground station, it could have two new stations, one at each end. The only logical western site is at Westkreuz, which would maximise tangential connections. Its only U-Bahn connection, however, is the planned U3. A new eastern main station could be built just west of Ostkreuz, or on the site of the old Görlitzer Bahnhof, now a park. Again, the Görlitzer Bahn could be connected to the Frankfurt line, with a Köpenick link line.

The complexity and scale of the project make an east-west tunnel unlikely, even if the money was available. An upgraded northern and southern Ringbahn could carry many east-west regional and inter-regional trains, relieving the Stadtbahn. By reserving the Stadtbahn for longer-distance services, and closing the regional stations at Charlottenburg and Alexanderplatz, it can also be more effectively used. (There is, after all, a parallel S-Bahn). By improving approach capacity, the existing north-south tunnel can also be more intensively used, but additional north-south capacity still seems preferable.

Upgraded line Neuruppin – Rathenow – Brandenburg

The railway network around Berlin, in the State of Brandenburg, is dominated by radial lines. Berlin itself has an inner ring railway, and an outer ring at the edge of the city. Further out, tangential lines were built: some of them as purely local lines, others as strategic freight routes avoiding Berlin. Two of these lines can be combined, to create an outer orbital line. This is one of a series of proposals, for new rail infrastructure north of Berlin.

The orbital line would connect three regional centres, at 60 to 70 km from central Berlin: Neuruppin, Rathenow and the city of Brandenburg. The line would also serve the smaller Neustadt (Dosse), restoring its role as a railway junction.

 
The route was built as two separate lines. The 69-km Neustadt – Brandenburg line (Brandenburgische Städtebahn), was built as a strategic freight line, also connected to the main Halle and Leipzig lines. The 29 km Neustadt – Neuruppin line was a local railway.

The route crosses four radial lines: the main lines to Hamburg, Hanover, and Magdeburg, and the secondary Prignitz line (Berlin – Neuruppin – Wittenberge). An upgrade of the Prignitz line was proposed here earlier. At present it is served by the RegionalExpress RE6, which stops at every station north of Kremmen. The three main lines carry intercity services, and also RegionalExpress lines – RE2, RE4, and RE1.

A restored Neuruppin – Rathenow – Brandenburg rail service would connect all these regional services, or their successors. It could connect at Neuruppin with the proposed regional rail line Neuruppin – Eberswalde, creating a long orbital route north of Berlin. At Neustadt, it would connect to the proposed regional rail line to Schwerin via Parchim, a long route over local railway lines

It is these existing and possible connections, which justify restoration of service, in a thinly populated rural area. At present, only the Rathenow – Brandenburg line is in use (RegionalBahn line RB51). The Rathenow – Neustadt line was abandoned, but only recently, so the alignment is still available. Since German reunification, many rural railway lines in the former DDR have been closed, as they were earlier in western Germany. In contrast to the roads, the lines were not upgraded, and the very slow trains also discouraged use. Before reopening, the line should be reconstructed to higher standards, and electrified. No new alignment is required: trains must reverse at Neustadt, but that does not make the route significantly longer.

Neustadt

Neustadt station is on the main line Hamburg – Berlin. It was historically a minor rail junction, and that function would be restored. The old local line from Neuruppin enters the station from the south-east. The line from Rathenow and Brandenburg crosses the main line on a bridge just outside Neustadt, and also enters the station from the south-east.

There was once a direct connection between both lines, avoiding Neustadt station, but the restored service is meant to provide good interchange. At Neustadt, the local lines once had their own station on the eastern side of the main line. There is still enough space for new separate platforms, which would be needed with more frequent regional services. (It is the main-line station which most needs improvement, since it has no through tracks for fast trains).

Rathenow

Rathenow station is on the main Hannover line, now upgraded to Berlin – Hannover high-speed line. The Brandenburgische Städtebahn always had separate platforms south of the main line, and a flyover toward Neustadt, so there is no conflict with the main-line tracks.

 
The present service level is poor, however. The ‘Regional Express’ line RE4 uses diesel trains on the electrified high-speed line, presumably to save money. This option is not compatible with frequent services. A new western rail link into Nauen from the Hannover line, was proposed here earlier.

 
For regional services, all parallel tracks would then be electrified, with an additional track through the Havelländisches Luch east of Rathenow. Alternatively, the intermediate stations (Nennhausen and Buschow) would be closed. Rathenow would then be served by inter-regional trains running non-stop from Nauen. Either way, the east-west connections from Rathenow would be much improved, especially with a restored link between Nauen and Potsdam and a new Nauen – Oranienburg service.

Brandenburg

Brandenburg station is on the main Berlin – Magdeburg line, which is also a main route to Hannover. Here too, the former Brandenburgische Städtebahn had its own station, on the north side of the main line, so there is no conflict with main-line trains. Brandenburg has a better service than Rathenow: Regional Express line RE1 offers an hourly service to Berlin, with extra trains in peak hours.

 
The former Brandenburgische Städtebahn continued south to Belzig, Treuenbrietzen and Jüterbog. This line is closed, and partially demolished. Even in the event of reopening, it would be preferable to operate it as a separate line. The restored services from Neuruppin and Rathenow would logically terminate at Brandenburg.

Stations and journey time

When the line was operational, it had 18 other stations and halts. Premnitz is the only other town on the line, with 8500 inhabitants. Havelsee and Rhinow have around 2000 inhabitants. Between Brandenburg and Rathenow, the line is close to the Havel river, with some recreational destinations. However, most of the line runs through farmland, with only very small villages. Inevitably, about half the stations will not re-open.

It is not worth re-opening the line, if the trains are as slow as in the past. With electrification and upgraded track and signalling, even a rural line can have an average speed of 80 km/h. Service frequencies must also be improved, with trains every 30 minutes. That means that all former passing tracks must be restored, and new ones added where necessary. Conditions have changed since the 1950’s, and these improvements are simply a minimum standard, for any rural rail line in western Europe.

New western rail link into Nauen

Nauen is on the main line Berlin – Hamburg, that is partially upgraded as a high-speed line (HSL). A new rail link into Nauen, from the Berlin – Hannover HSL, would allow rationalisation of services. In combination with new infrastructure between Nauen and Potsdam, and a new regional rail service Nauen – Oranienburg, it would create a new regional rail junction. The region is thinly populated, and Nauen itself is a small town (population 16 000), but there is no other suitable location.

The Hannover – Berlin high-speed line was built on a pre-existing alignment (Lehrter Bahn), which is still in use for other trains. The result is, in effect, two parallel railway lines, one partly electrified. Stendal has a separate bypass for high-speed trains, on the right in the image below.

HSL bypass of Stendal starting at Möringen: image by Sebastian Terfloth under CC-SA-3.0 licence…

However, east of Rathenow, there is a 17-km section without parallel track. This low-lying area (Havelländisches Luch) is the main German habitat of the Great Bustard, the largest flying bird in Europe. The species is so endangered that a tunnel was considered, and the line was designed to prevent train-bird collisions. On this section there are two stations, serving small villages, Nennhausen and Buschow. Both have through tracks for high-speed trains, but it is still unusual for a high-speed line.

This solution works at present, because train frequency is low. The hourly Regional Express line RE4 runs Rathenow – Berlin – Ludwigsfelde – Jüterbog, sometimes starting at Stendal. Despite the name, it stops at all stations to Spandau. West of Rathenow, RegionalBahn line RB13 runs to Braunschweig, via Stendal, Oebisfelde and Wolfsburg (every two hours, hourly from Stendal on weekdays). Since not all track is electrified, it uses Desiro diesel units. Stendal is also served by some Intercity trains, but only one at regular intervals: the two-hourly Berlin – Amsterdam service.

With the opening of the proposed Wustermark – Nauen link, regional services from Spandau via Staaken, Dallgow-Döberitz, Elstal and Wustermark could terminate at Nauen, 35 km from central Berlin. Regional and inter-regional trains for stations further east could also use this link, if they can turn back to the Hannover line. That is the logic of the link line proposed here, west of Nauen. The diversion via Nauen would add about 5 km to the route, but improve interchange.

The new link does not dictate a service pattern. The present services (Regional-Express to Rathenow, RegionalBahn from there to Braunschweig), could be retained. However, it is logical to combine the new link with full electrification of the parallel tracks, and an additional track through the Havelländisches Luch.

That would allow three levels of service: a non-stop ICE Hannover – Berlin on its existing route, an inter-regional service via Wolfsburg, Stendal and Nauen, replacing some present Intercity services, and regional services for the remaining stations. With a new grade-separated junction on the Berlin side, Rathenow could also be served by the inter-regional trains. Regional services could run west from there, as at present, or they could be split into Hannover – Stendal and Berlin – Stendal lines. (Stendal is the junction with the north-south line Wittenberge – Magdeburg).

Another option is to close the stations at Nennhausen and Buschow. The area served is Amt Nennhausen, with only 4750 inhabitants, and a density of under 20 persons/km². With closure of the last intermediate stations, Rathenow would be served by inter-regional trains running non-stop from Nauen.

The new western link to Nauen would start at Gross Behnitz, east of the Havelländisches Luch. It would pass between Lietzow and Nauen, and join the Hamburg line just west of Nauen station. The line crosses forest and farmland, and there are no obstacles to construction.

The new link would be 10 km long. It would have no intermediate stations, and the new route does not displace any other station. (Neugarten and Gross Behnitz stations are closed).

East of Nauen, some trains could use the Hamburg line to Spandau: the proposed upgrading of the line includes four tracks from Nauen. For all these services on the Hamburg and Hannover lines, Nauen would be an interchange station, with additional services to Potsdam and Oranienburg. An additional option is a new link line to Brandenburg, diverging from the Nauen – Wustermark link.

Regional rail service Nauen – Oranienburg via BAR

This regional rail service Nauen – Oranienburg is part of a series of proposals for the triangle Hamburg – Berlin – Szczecin. In this case, the new infrastructure is minimal: improvements to the junction at Falkenhagen (Falkenhagener Kreuz). Nauen is on the Berlin – Hamburg main line, and the junction connects that line to the outer ring line (Berliner Aussenring, BAR). The new service would use the ring line towards Oranienburg.

The proposal is complimentary to the new rail link Nauen – Potsdam (previous post). Both are orbital services along the BAR, starting at Nauen. However, Potsdam is a medium-sized city, inside the ring line. The Potsdam route (in orange on the diagram) would serve four stations there, with good connections to the south-west quadrant of Berlin.

The Oranienburg service (in green) turns away from the BAR, and serves fewer people. Trains would probably not stop at the three S-Bahn stations near Oranienburg (see below), and connections to the north-west quadrant of Berlin are limited. With another new link from the Hannover main line, the small town of Nauen would become a regional rail junction, and the line to Oranienburg would still be a useful connection.

This is not the only possible route between Nauen and Oranienburg. There was a 38-km railway line between the two, via Kremmen, part of an western bypass of Berlin. Because the line was intended for freight, it served few villages, and that limits the benefits of re-opening. Nevertheless, it would be shorter than the route proposed here.

Infrastructure: Falkenhagener Kreuz and BAR

The proposed additional upgrading of the Berlin – Hamburg line included four tracks between Nauen and Spandau. That could be a parallel S-Bahn, but only a four-track main line is compatible with new regional services. The new service to Oranienburg would use the additional tracks, on the 9 km from Nauen to the junction at Falkenhagen. There is one intermediate station, Brieselang, which already has four tracks.

At Falkenhagen, a new single-track grade-separated link would connect the four-track main line to the BAR. The new link would be in tunnel, since there is already an overbridge (L202 road), but would follow the existing curve. From there, trains would use the BAR ring line, to the junction at Hohen Neuendorf.

 
Unlike the existing regional line RB20 (Oranienburg – Potsdam), the line would not divert to Hennigsdorf to connect with the S-Bahn. There is a disused interchange station on the BAR at Hennigsdorf Nord: it would allow interchange with either an extended S-Bahn, or a regional service. (See the earlier proposals for the Berlin – Neuruppin – Wittenberge line). This station would by mainly for interchange: the station site itself is isolated.
 

 
There is one more station on the BAR, at Hohen Neuendorf West. Immediately after the station is the junction with the northern main line to Rostock, the Nordbahn. The junction is already grade-separated, with an additional underpass under the S-Bahn tracks.

The new service would continue via the Nordbahn main line, to Oranienburg. At present there are no intermediate stations on this section, and it would be better to keep it that way. In that case, the orbital service would have no connection southwards to the S-Bahn lines S1 and S8, and that reduces its utility. Possibly, the line could serve new platforms, on the main line at Birkenwerder, There is enough room for them, and for through tracks. An alternative is to use dual-system trains, serving the S-Bahn stations at Birkenwerder, Borgsdorf, and Lehnitz, but that would require a new grade-separated junction at Hohen Neuendorf. Without either of these options, the alternative route from Nauen to the northern suburbs of Berlin, is via the regional station at Gesundbrunnen.

S-Bahn network: map by Maximilian Dörrbecker under CC 3.0 licence…

At Oranienburg (population 42 000), the new service would connect to high-speed trains on the proposed Berlin – Rostock high-speed line (HSL). That project assumes restoration of the old Nordbahn route though Berlin, which has been planned for decades. The line would also connect to regional services north from Berlin, and to the proposed regional rail line Oranienburg – Eberswalde.

This is a classic orbital rail service: Nauen and Oranienburg are on the outskirts of Berlin, 30-35 km from the city centre. The route is 41 km long, and with only three intermediate stations, journey time could be around 25-30 minutes. For dual-system trains using the S-Bahn into Oranienburg, journey time would be 5-6 minutes longer.