Originally a Catholic cathedral and today a Reformed Protestant church , it was built between 1019 and 1500 in Romanesque and Gothic styles . The late Romanesque building , destroyed by the 1356 Basel earthquake , was rebuilt by Johannes Gmünd , who was at the same time employed for building the Freiburg Münster . Ulrich von Ensingen , architect of the towers at the Ulm Minster and the Strasbourg Cathedral , extended the building from 1421 . Hans von Nußdorf completed the southern tower in 1500
1356 Basel earthquake
1356 Basel earthquake
Basel Minster