Until 1990, the Inner German Border ran through the western third of the Harz. The Brocken plateau and other peaks near the border were part of a large military out-of-bounds area, which demonstrating walkers first entered on 3 December 1989. Tourism on the Brocken has since then become very intense - about 1.3 million people visit the summit of the Brocken annually. The former out-of-bounds area today has many habitats worth protecting and, as a result, it is being turned into a green belt.