This urban-regional line (S-Bahn) is an addition to the proposed Budapest urban-regional metro. It would use the existing alignment of the line out of Nyugati pályaudvar (Western Station, in fact north of the city centre) to Kőbánya-Kispest Station. This is the first section of Hungarian rail line 100, Budapest – Szolnok – Debrecen. At first it runs north-east, but then turns almost 90°, and continues south-east.
Trains would start at Nyugati Station, on the surface. The proposed north-south S-Bahn line would also pass through here, but a connection is not logical: it would mean a U-turn. The line proposed here is a tangential line, not a radial line. Part of the route would be shared with an east-west S-Bahn line coming from Keleti Station. Another brach of the east-west line would cross the tangent line: in theory, a station could be built at the crossing, but the location is not good.
At Kőbánya-Kispest Station, the line would allow interchange with the proposed southern tangent S-Bahn line from Kelenföld Station, and with the proposed ring S-Bahn line. The map below show the relationship between the lines: east-west lines out of Keleti in blue, east tangent in orange, south tangent in green. It assumes a new link tunnel east of Keleti station (blue dotted line).
Line and stations
The existing line is double-track: an intensive urban service requires 4 tracks, separation of local and long-distance traffic, and a complete upgrade. At present the line has two intermediate stations: Budapest-Zugló and Kőbánya alsó. There are three possible locations for new stations.
2 km from Nyugati Station, the north-east to south-east curve must be improved, and the junctions grade-separated. If the curve permits, there could be a new station here, alongside the Mexikói út metro station. This is the current terminus of metro line 1. A short extension is planned, to Rákosrendező station, on the main line north from Nyugati to Vác.
A new station at Kerepesi út would give some interchange with metro line 2 It would be half-way between Stadionok and Pillangó utca stations, about 400 m from each.
Further on, the tangential line crosses the main line to the east, out of Keleti station, line 120. Instead of a station on the crossing, which is relatively isolated, the best option is new tunnel, linking Keleti Station to the tangent line. All urban traffic, between Keleti and Kőbánya-Kispest , would run via this tunnel. It would not be an easy project, because of the limited space: two schematic alignments are shown…
A logical new station on the shared section, would serve the exhibition and conference centre Hungexpo. It would be located directly opposite the main entrance. From there, it is 1400 m to the existing Kőbánya alsó station.
The remaining section to Kőbánya-Kispest Station is about 2800 m long, but there is no good location for an intermediate station. At Kőbánya-Kispest itself, there is interchange with main-line trains, and it is the current terminus of metro line 3. The station would need reconstruction, to accommodate the proposed new lines, including new lines through Budapest Ferihegy airport, and the extra traffic.
The exact pattern of services beyond Kőbánya-Kispest is not considered here. The proposed S-Bahn network would have several lines entering Kőbánya-Kispest Station, and several leaving it. Which is best connected to which, is a matter for detailed traffic analysis.