Basel Cathedral was built between 1019 and 1500 in Romanesque and Gothic style. The cathedral obtains its recognizable red colour thanks to the red sandstone used for its construction. The old Catholic church became Protestant during the 16th century.
The Synagogue of Basel first opened in 1868 and was constructed by the architect Hermann Gauss. It is modelled after the synagogue in Stuttgart with neo-Byzantine, Moorish, and Romanesque stylings. In renovations, the synagogue has been enlarged, a second dome has been added, and the walls have been painted grey before being recently restored to colour.
The church of St. Fridolin was built between 1821 and 1822 according to the plans of the architect Christoph Arnold and bears a strong resemblance to the pilgrimage church of Bad Rippoldsau-Schapbach, built in 1829. The exterior of the church is neo-classical, while the interior is classicistic, enriched with rococo elements.