Three medieval structures, united in the 16th century, form this surprisingly fun municipal museum. Renovations completed in 2019 have modernized its displays on Dinan’s history dating back to prehistory, and now there are a number of entertaining interactive elements and lots of wall text in English. The chapel contains holy artifacts, furniture, and silver. The dungeon of the colossal 14th-century fortress was a residence for the Duke of Brittany before being converted into a jail.