The island's main cultural-history museum, set in a 19th-century town house on Sankt Mortensgade just off the main square. The collection runs from prehistoric finds, through medieval shipwrecks, to Bornholm's distinctive 18th-century longcase clocks ("Bornholmer-ure") and the dramatic Soviet bombing of Rønne in May 1945. The toy collection on the upper floor is unexpectedly good.
It is a small, well-curated museum — you can do it properly in about ninety minutes. English labels throughout. Combined tickets are sold with the other Bornholms Museum sites at Erichsens Gård and Hjorths Fabrik nearby.