Dreirosenbrücke, Double-decker truss bridge in Basel, Switzerland

The Dreirosenbrücke is a steel composite truss bridge over the Rhine in Basel, built as two parallel bridges each 14.90 m wide, with spans of 77, 105 and 84 m on two piers that incorporate the piers of the 1934 bridge. The lower level carries the A3 motorway in a closed, sound-insulated vault; the upper level serves local traffic, trams, cyclists and pedestrians, with a roughly 10 m wide boulevard on the southern side.

The name comes from a nearby property called 'To the three roses' owned by the Iselin family, who displayed three white roses on their coat of arms. The bridge became an important crossing and has since shaped the connection between the two city districts.

The bridge links two distinct neighborhoods and creates a place where people naturally gather and interact. It plays a role in daily life for those moving between Kleinbasel and Grossbasel.

The motorway runs in a closed, sound-insulated vault on the lower deck, so through traffic stays off the local level. Cars, trams, cyclists and pedestrians use the upper deck, where the tram tracks are separated from individual traffic. The roadway and tram alignment are shifted north, leaving a roughly 10-metre-wide boulevard for pedestrians on the southern side.

This is the last Rhine crossing within Swiss territory, where the river forms the national border. This location gives it a special role in shaping border traffic routes between Switzerland and Germany.