Two well-known running events pass over the Brocken: the Ilsenburg Brocken Run (beginning of September, , of which uphill, has taken place since the 1920s) and the Brocken Marathon which is part of the Harz Mountain Run with its start and finish south of Wernigerode. Both start in the valley, climb the Brocken and return. The most challenging part in each case is the last four kilometres to the Brocken summit, for which in both races, a separate mountains classification is given. This section is a concrete slab track with a steady incline of about 20% and the runners are exposed above the tree line, often to a sharp, icy wind. Of the just under 1,000 people who usually achieve it, only 50 negotiate this section without stopping to walk.