South of the Ruhestein the Schwarzwaldhochstrasse runs along the high ground between the Schliffkopf and the Kniebis plateau, and the forest feels wilder here than further north. Much of this ridge lies in the Black Forest National Park, created in 2014, where large areas are being left to grow without forestry. You see the results from the saddle: grey snags of storm-felled trees, dense young growth, open patches of heather and grass on the old high pastures called Grinden, where cattle once grazed. It is not a manicured landscape, and that is the point.
The road is fast and open along the crest, with long curves and good sightlines, and in places the trees fall away to give you views east over the endless wooded ridges of the Black Forest and west toward the Rhine. The Schliffkopf has a hotel and a car park with a fine outlook, and the Kniebis at the southern end has a scattering of guesthouses and was once a fortified pass where armies crossed between the Rhine and the Danube valleys. Old earthworks, the Schwedenschanze, date back to the Thirty Years' War and later conflicts.
Just below the ridge to the west lie the Allerheiligen waterfalls and the ruins of the Allerheiligen monastery, a Premonstratensian house founded around 1200 in a deep side valley. The roofless Gothic walls of the church stand among the trees, and the falls drop through a narrow gorge in a series of cascades with steps and walkways beside them. It is one of the most atmospheric places in the northern Black Forest, and the road down to it is narrow, twisting and steep, a good test of low-speed control. From there the valley continues down to Oppenau, a small town of about five thousand people in the Rench valley.
Weather matters at this height. Fog often sits on the crest when the valleys are clear, and in spring and autumn wet leaves and damp patches linger in the shady bends. The ridge is popular with bikers in summer and the police are a regular presence. For fuel, food and supplies, drop down to Oppenau or further to Oberkirch, a larger town of about twenty thousand known for its fruit brandies, or east to Freudenstadt, whose huge central market square is one of the largest in Germany. Bad Peterstal-Griesbach, a small spa town with mineral springs, is another quiet option for coffee on the way south.