Mummelsee is a small, round, black lake in a hollow beneath the Hornisgrinde, the highest peak in the northern Black Forest at about 1,160 metres, and nearly every German has heard of it because of what lives there. According to the legend, the lake is home to the Mummel, water nymphs who dance on the surface at night, and to a lake king who holds court in a crystal palace on the bottom. Anyone who throws a stone in will cause a storm, and a few unwary visitors are said to have been pulled down. The old stories have given the place a quiet reputation for trouble, and the dark water does nothing to discourage it.
In reality, the lake is a cirque left behind by a glacier in the last ice age, roughly seventeen metres deep and surrounded by spruce. It sits beside the Black Forest High Road, the B500, which runs along the ridge from Baden-Baden to Freudenstadt and dates from the early twentieth century, and a large hotel, a restaurant and a car park crowd the shore. On a sunny weekend, the place is busy with coaches, motorcyclists, families on pedal boats and people photographing the carved wooden Mummel figures near the water. The best time is early morning or a weekday in autumn, when you will have the shore nearly to yourself.
The ride to the lake is a classic. The B500 climbs from the Rhine plain near Bühl or from the Acher valley, through dense forest and past viewpoints, with tight bends and tunnels of trees that give way to open ridge. Up on the heights, the road is a long, rolling line with views over the Rhine plain on one side and the forested Murg valley on the other. The surface is smooth, and the speed limits and the number of other riders mean that a relaxed pace is the most enjoyable. In bad weather, fog can reduce visibility to a few metres and make the lake look even more sinister.
The nearest services are in Kappelrodeck, Achern or Bühl on the plain side, and in Baiersbronn to the south. The restaurant serves hearty food, including the local trout and Black Forest ham, and a slice of cherry cake helps to take the chill off.
Walk to the far shore and look back at the lake, and you will see why the legends took hold.