The castle museum is spread across four exhibition spaces around Klaipėda's castle – two of these are located in atmospherically lit tunnels and deal with the history of the castle and of Klaipėda as a port city; another features changing exhibitions of contemporary art. The highlight, however, is the Museum 39/45 (separately priced; adult/child €1.74/0.87), a high-tech depiction of WWII and its impact on the city.
Originally built by the Teutonic Order in the 13th century, moat-protected Klaipėda Castle has a storied history befitting the region's turbulent past. Razed and rebuilt on multiple occasions, the castle was almost entirely destroyed in the late-19th century. It languished in disrepair until mid-20th-century archaeological excavations (still ongoing) renewed interest in the castle.