The museum is located in the former Town Hall in Lossiplatsi Square. It exhibits the history of Haapsalu and Läänemaa from the pre-Christian era right up to Haapsalu's success as a resort town in the 1930s. Displays include the recreated interior of an early 20th-century farm dwelling, a ship and the pre-war mayor's office.
Built around AD 90 to entertain the legionaries stationed at the fort of Caerleon (Isca), the impressive amphitheatre was the Roman equivalent of today’s multiplex cinema. Wooden benches provided seating for up to 6,000 spectators, who would gather to watch bloodthirsty displays featuring gladiatorial combat and exotic wild animals.
Long after the Romans left, the amphitheatre took on a new life in Arthurian legend. Geoffrey of Monmouth, the somewhat imaginative 12th-century scholar, wrote in his History of the Kings of Britain that Arthur was crowned in Caerleon and that the ruined amphitheatre was actually the remains of King Arthur’s Round Table.
Today it is the most complete Roman amphitheatre in Britain.