The Archaeological Museum of Monemvasia.
A must-visit, this museum is housed in a 16th-century building constructed by the Turks. Located in the castle, it was originally a Muslim mosque before taking on a number of different roles, including being a Frankish and a church prison. Today, it showcases an impressive archaeological collection that includes the remains of temples, walls, homes and a fortress as well as a wide range of items used in daily life, ceramic objects and sculptures.