Osnabrück is a city in northwest Germany. The Town Hall is where the 1648 Peace of Westphalia was negotiated, bringing the 30 Years' War to an end. It sits on the market square, along with gabled houses and St. Marien, a 13th-century Gothic church. The Felix Nussbaum House shows a large collection of works by the local surrealist painter. To the south, the grounds of Osnabrück Castle are a venue for summer concerts.