Berlin has a racetrack hidden in plain sight. The AVUS, which opened in 1921 through the Grunewald forest, was both one of the first motorways in the world and a racing circuit, where drivers and riders competed at astonishing speeds on its long straights and steep, banked north curve. Racing ended long ago and the banking is gone, but the road is still there, now part of the A115 motorway, and the old grandstand and timing tower survive by the roadside. Passing them on the way into the city is a nod to history.
You end on the edge of the Grunewald, Berlin's largest forest, a vast area of pine and oak woods on the western side of the city, bordered by the Havel river and dotted with lakes. Berliners come here to walk, cycle, swim and escape the city, and on summer weekends the lakes, like the Krumme Lanke and the Schlachtensee, are full of swimmers. In the middle of the forest, the Teufelsberg, a hill built from the rubble of wartime Berlin, is crowned by the ruined domes of an American listening station from the Cold War.
There is also a sombre memorial. At Grunewald station, Platform 17 was one of the main departure points for the deportation of Berlin's Jews to the ghettos and death camps during the Second World War, and steel plates along the platform record the dates, numbers and destinations of the transports. It is a quiet, powerful place.
The rides that end here come back from the Harz mountains and Saxon Switzerland, long days that finish with motorway miles into Berlin. The Grunewald and the western suburbs offer a calm end to the ride, with tree-lined avenues and villas, but Sunday evenings bring the whole city home at once. Fuel and restaurants line the main roads, and the beer gardens by the lakes are a fine place to unwind.