Before it was a motorway, the A115 that runs past Zehlendorf was the AVUS, a dead-straight test and racing road opened in 1921, where Mercedes and Auto Union raced in the 1930s on a steeply banked curve that terrified drivers. The banking is gone, and the road is just a busy stretch of the Berlin motorway network, but its history adds a little spice to finishing a ride here.
Zehlendorf is the green, leafy south-west of Berlin, a district of villas, gardens and forests. The Grunewald, a large forest, stretches to the north, and the lakes of the Havel and the Grunewald chain, Schlachtensee, Krumme Lanke and Wannsee, are within easy reach. In summer they are packed with swimmers, and the paths around them are busy with walkers and cyclists.
Dahlem, next door, is home to the Free University and the Botanical Garden, one of the largest in the world. The Onkel Toms Hütte estate, designed by Bruno Taut in the 1920s, is one of the modernist housing estates listed as a World Heritage site, with colourful facades and gardens.
Coming back from the Fläming, the final stretch into Berlin follows the motorway or the old roads through Potsdam. Traffic can be heavy, especially on Sunday evenings, and Berlin's speed cameras are numerous.
On a hot evening the lakes win over everything else. Park near the Schlachtensee, swim out from the wooded shore, and then find a beer garden; fuel and food in Zehlendorf are only a few minutes away when you are ready.