Barmen is a former industrial metropolis of the region of Bergisches Land, Germany, which merged with four other towns in 1929 to form the city of Wuppertal. Barmen was the birthplace of Friedrich Engels and together with the neighbouring town of Elberfeld founded the first electric suspended monorail tramway system, the Schwebebahn floating tram. Barmen was a pioneering centre for both the early industrial revolution on the European mainland, and for the socialist movement and its theory. It was the location of one of the first concentration camps in Nazi Germany, KZ Wuppertal-Barmen, later better known as Kemna concentration camp.