Rheinfelder Brücke, Prestressed concrete road bridge in Aargau, Switzerland.

The Rheinfelder Brücke is a modern road crossing made of prestressed concrete that spans more than 200 meters. Its construction uses prestressed concrete elements designed to handle regular traffic with a slim and efficient structure.

Construction began on 18 June 2003, carried out by Wayss & Freytag, and the bridge opened to traffic on 7 March 2006. It was built to relieve Kaiseraugst and both Rheinfelden of through traffic and to offer an alternative to the Basel–Weil am Rhein border crossing. After its opening, the Alte Rheinbrücke was closed to motor traffic except taxis, buses and vehicles unfit for motorways.

The bridge carries about 33,000 vehicles a day and was built to divert shopping and heavy-goods traffic away from Kaiseraugst and both Rheinfelden. Since it opened, the Alte Rheinbrücke upstream has been closed to general traffic, except taxis, scheduled buses and vehicles unfit for motorways. A foot and cycle path runs along its east side.

Pedestrians and cyclists cross on a footbridge attached to the east side of the bridge. The Swiss motorway feeder from the bridge to the Rheinfelden-West junction is exempt from the vignette, so the Swiss customs post can be passed without one. Since the bridge opened, the Alte Rheinbrücke has been closed to general traffic, except taxis, scheduled buses and vehicles not fit for motorways.

The bridge rests on piers founded in closed sheet-pile boxes driven into the riverbed, their reinforcement cages pre-woven on land and placed by divers. It is often said a planning error nearly left a gap where the two cantilevers met, but that mishap actually occurred on the Hochrheinbrücke upstream, caused by a sign error in elevation reference points.