The Middle Bridge (German: Mittlere Brücke [common name] / German: Mittlere Rheinbrücke [official name], French: Pont du Milieu) is a historic bridge in the Swiss city of Basel. It is situated on the oldest existing bridge site across the Rhine, between Lake Constance and the North Sea. It also marks the boundary between the High Rhine (Hochrhein) and Upper Rhine (Oberrhein/Rhin Supérieur) sections of the river.

The first document pertaining to the Middle Bridge dates back to 1223. A loan document of that year shows that the bishop Heinrich of Basel (also known as Heinrich von Thun) temporarily transferred the cathedral treasury to a Jewish moneylender as deposit for a loan. The money was to be used for the construction of the Middle Bridge, the first bridge across the Rhine in Basel, which played a significant role in the development of trade in the city. The exact time of construction is unknown, but it must have been complete to a certain extent in 1224, since a document of that year mentions “Johannes on the Rhine bridge.”

In two documents from 1225, the monasteries of St. Blasien and Bürgeln are exempted from the bridge toll in return for their financial contributions. For mules, horses and goods crossing the bridge, there was a toll of 30 silver marks, which the bishop appropriated until the debt to the Jews of Basel was paid off.

The bridge gave the city a tremendous economic boost, and following its construction, the villages of Niederbasel and Oberbasel formed the fortified town of Kleinbasel on the eastern banks of the Rhine. It was united with Grossbasel in 1392.

Between 1903 and 1905, the old bridge underwent a renovation project during which it was rebuilt entirely out of stone. The new construction was named «Middle Rhine Bridge». The old bridge was simply named the «Rhine Bridge» back when it was the sole bridge in Basel crossing the river; later, when the Wettstein and Johanniter bridges were built, it became known as the «Old Rhine Bridge». The name «Middle Rhine Bridge» was chosen because three bridges spanned the Rhein in Basel at the time, and this one was situated in the middle of the other two bridges.

The bridge is 192 meters long and 18.8 meters wide and is built out of granite from the north face of Saint-Gotthard Massif. The construction was undertaken by Albert Buss & Cie. from Pratteln and Philipp Holzmann from Frankfurt am Main, and cost 2.67 million Francs. The bridge features seven arches - six of which stretch across the Rhine, and one which stands over the riverside footpath on the New Town side. A reproduction of the bridge's Brückenkapelle known as the Käppelijoch, was built over the central support of the bridge. The bridge is a great work of historic bridge construction in Switzerland. Architectural and city planning deliberations played a decisive role in the choice of building materials and general design to be used for the bridge: in order to avoid interfering with the image of the old town, Emil Faesch from Basel was chosen to build the stonework of the bridge, while Friedrich von Thiersch from Munich was chosen to build its modern iron truss skeleton.

In order to avoid disrupting traffic over the Rhine, a temporary replacement bridge was constructed over twelve wooden truss supports a few meters away from the original bridge. The completed Bridge was unveiled to the public on the 11. November 1905 during a fair.

The bridge was refurbished with no alterations made to its appearance in 2002.