The first phase of the Bamberg town hall was completed by 1467 on the river Regnitz. Originally in a Gothic style, it was rebuilt in Baroque and Rococo style by Johann Jakob Michael Kchel in 1744-1756. Anwar Johann painted the murals on the exterior walls (1755). Traditional German fachwerk (a half-timbered wing called the Rottmeisterhuschen used for guards on watch) juts out over the river. The town hall is built on an artificial island linked on either side by a bridge (the Obere Brcke). This is because of conflict between the bishop and the mayor, with the bishop refusing land for the hall. Today it is the Sammlung Ludwig, a museum that houses one of the biggest porcelain collections in Europe.