The Walchensee is one of the deepest and clearest Alpine lakes in Germany, and the road along its eastern and southern shore is one of the most photographed in Bavaria. The water is a turquoise that looks almost Caribbean when the sun hits the shallows, and it is fed by cold springs, which keep it chilly all summer. Around it rise forested slopes, the Herzogstand to the north and the peaks of the Karwendel and the Estergebirge to the south, so the lake sits in a bowl, with its surface often creased by wind.
That wind is the lake's trademark. In summer the thermals draw a steady breeze along the water in the afternoon, and the lake is a favourite of windsurfers and kitesurfers, whose coloured sails dot the surface. For a rider the wind means gusts that push across the road on the exposed stretches, and the bike will feel it. The road itself, the B11, is smooth, with long bends and short straight sections close to the water, and the lake appears and disappears between trees. There are a number of pull-offs, though on summer weekends they fill early and the road gets busy with cars and cyclists.
Something remarkable lies under the mountain above. The Walchensee power station, built in the 1920s, uses the drop of about two hundred metres from the lake down to the Kochelsee to generate electricity, and it was a major engineering project of its time, associated with the engineer Oskar von Miller. You can visit the plant in season, and the pipes running down the hillside are visible from the road above Kochel.
The nearest towns are not on the lake: Schlehdorf, with its handsome church and a convent on a hill above the Kochelsee, is about seven kilometres away, and Murnau am Staffelsee, with nearly twelve thousand people and the fuel and supermarkets you want, is thirteen kilometres off. Murnau was the home of the painter Gabriele Münter, whose house became a gathering place for the Blue Rider painters. A small village on the Walchensee itself offers cafes with lake views and a plate of grilled lake char, a regional speciality. Come early in the day, before the beach crowd arrives, or late in the evening, when the lake loses its wind and turns to glass.