The Vouvalis Mansion is a three-storey building with underground storage vaults. There are eight rooms on the ground floor, five on the first floor and another five on the second floor.It was built in two stages: the original structure was smaller, part of the dowry of Katherine Pelekanos, who married Nicholas Vouvalis, the wealthiest sponge-merchant of his time on Kalymnos. Vouvalis modified and enlarged it in the 1890s, also adding the second floor.
Today the Vouvalis Mansion, with furnishings of the period in the dining room, the salon and the owner's office, is open to visitors (of may be seen by arrangement). Other rooms are used for the storage of archaeological finds.