The City S-Bahn is a 5,380 metre-long tunnel section of the Hamburg S-Bahn. It runs between Altona station and Hamburg Hauptbahnhof through the city centre of Hamburg and the districts of Altona and St. Pauli. The S-Bahn lines S1, S2 and S3 of the Hamburger Verkehrsverbund run through the tunnel. Seven S-Bahn stations are located in the tunnel, including the tourist-oriented stations of Landungsbrücken and Reeperbahn.

Jungfernstieg is an underground railway station in the city centre of Hamburg, Germany, served by the underground railway (U-Bahn) and the suburban railway (S-Bahn). The station is one of Hamburg's busiest rapid transit hubs.