It is housed in one of the finest neoclassical buildings of Kalymnos at the harbor and is open to the public since 1994. Its collection includes exhibits on local maritime history and sponge diving, while hosting several items from ancient shipwrecks. There are also photographs, full traditional diving equipment, sponge processing equipment, even some sponge-diving vessels that were withdrawn. In the same building lies the Folklore Museum with remarkable exhibits from the local folk culture.