Kassel is a city in central Germany. It's known for its Documenta art exhibition. Bergpark Wilhelmshöhe is a sprawling park dating back to the 18th century. It's home to Wilhelmshöhe Palace and its Old Masters Picture Gallery. The neo-Gothic Löwenburg castle displays 16th- and 17th-century weapons. The Herkules Monument offers city views from atop the baroque Wasserspiele water features, which cascade down a hill.