Basel’s medieval cathedral is located on the ‘Münster Mount’ high above the river Rhine. The Romans had a fortress on this hill, which had been inhabited even before that. The Bishopric of Basel was founded in 343. The original Episcopal residence was at Augusta Raurica, a large Roman military camp some miles southeast of Basel. In the early Middle Ages, the bishop moved to Basel.
Basel’s first cathedral was built by bishop Haito (805-823). A larger building named Heinrichsmünster after German King Henry II was consecrated in 1019. A new church building in late Romanic style was erected between 1220 and 1230, but almost completely destroyed during the great Basel earthquake in 1356. This building was restored using basically the same ground plan, but with some new elements in Gothic style. The towers were erected in 1429 (Georgsturm, northwest) and 1500 (Martinsturm, southeast). During the Reformation the bishop was expelled from the city.