Malbork Castle is the largest Gothic castle in Europe, and the largest brick castle in the world (once housing over 3,000 soldiers). It was built by the Teutonic Knights in 1276 and later became their headquarters and capital in the early 14th century. After many centuries of turmoil and being captured by different powers, it was badly damaged after serving as a German POW camp in World War II. It has since been completely restored and is now a UNESCO World Heritage site. Admission comes with a mandatory three hour long tour in Polish. You can purchase an English guidebook at the kiosks or arrange an English tour in advance. The tour passes through the three sections - the High, Middle, and Low Castles and will show you an impressive weapons collection and one of the world’s best collections of amber artifacts.