Heritage Site. It features many valuable remnants of the Hanseatic time, Brick Gothic, renaissance, baroque, historicist and Jugendstil buildings. The heart of the old town is the Alter Markt Square ("Old Market"), with the Gothic city hall (13th century). Behind the city hall soars the imposing St. Nicholas' Church, built in 1270–1360. The square is surrounded by houses from different periods, including the Gothic Wulflamhaus (a 14th-century patrician house, today a restaurant), and the Baroque Commandantenhus of 1751, the old headquarters of the Swedish military commander. Saint James' Church, built in mid-14th century. It was destroyed several times, e.g. by Wallenstein and in World War II. Saint Mary's Church, built in 1383–1473 in Gothic style, is the largest church in Stralsund, and from 1625 to 1647 it was the world's tallest structure. Its octagonal tower (104 meters high) offers a panorama view of Stralsund and the neighboring islands of Rügen and Hiddensee. St. John's Abbey (Franciscan monastery built in 1254) is one of the oldest buildings in the city. Stralsund is the port of registry for the former German Reichsmarine Navy Sail Training ship "Gorch Fock" 1. It is now a floating museum. The Monastery of Saint Catherine, mainly built in the 15th century, houses two museums today: Stralsund's Museum of Cultural History (known for e.g. the Gold Jewellery of Hiddensee), and the German Oceanographic Museum, Germany's largest aquarium and oceanographic collection. The ancient refectory of the monastery is one of the most spectacular Gothic interiors in Germany. Besides the mentioned German Oceanographic Museum at the Katharinenkloster, Stralsund has other museums dedicated to marine life, including the popular Ozeaneum that was voted European Museum of the Year in 2010. There is also a nautical centre, the Nautineum, on Dänholm island and the Marinemuseum Dänholm, showcasing the military history of the German Navy, especially the interwar Reichsmarine. It also hosts one of the last remaining GDR Volksmarine (People's Navy) torpedo boats. Buildings and monuments Old Town (Altstadt) The centre of Stralsund has a wealth of historic buildings. Since 1990, large parts of the historic old town have been renovated with private and public capital, and with the support of foundations. As a result of the contempt for historic buildings in East Germany many houses were threatened by ruin. The Old Town in particular offers a rich variety of historic buildings, with many former merchants' houses, churches, streets and squares. Of more