Stadtmuseum Rapperswil-Jona is a museum of local history and art in Rapperswil, canton of St. Gallen in Switzerland.
The museum is situated in three Middle Ages buildings, remains of a former castle as part of the town walls of Rapperswil, as of today in the so-called Breny house, a keep, and in the Breny tower and an intermediate section that was a battlement of the town wall at Herrenberg hill. The buildings are situated between Schloss Rapperswil, Stadtpfarrkirche Rapperswil and Engelplatz square.
Breny house and Breny tower are part of the remains of the northeastern town walls of the medieval city of Rapperswil. The buildings date back to early 13th century AD, when the lords of Russikon (Russinger) built a residential tower respectively a small castle as servants (Ministerials) of the Counts of Rapperswil. In its present form, it was built in 1492 by the knight Hans of Landenberg from the Töss Valley replacing the former seat of the lords of Russikon. The Landenberg family officiated in Rapperswil as mayors and councils to 1530. Subsequent occupants were from 1530 to 1660 the Göldlin family, then the Good family, and from 1758 the Breny family. The former castle with its 28 metres (92 ft) high residential tower at the so-called Herrenberg ("castle hill") marked in the 16th century the urban expansion of the Middle Ages city to the northeast. The buildings were part of the northeasterly town walls at the bay of Kempraten on Lake Zürich shore heading to the so-called Herrenbergtor gate (broken in 1848).