Hemer is a town in the Märkischer Kreis district, in North Rhine-Westphalia, Germany. Hemer is located at the north end of the Sauer…Hemer is a town in the Märkischer Kreis district, in North Rhine-Westphalia, Germany. Hemer is located at the north end of the Sauerland near the Ruhr river. The highest elevation, at 546 metres, is in the Balver Wald in the south of the city. The lowest elevation, at 160 metres, is at the Edelburg in the northeast.