Think of
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Get Active Outside

If inline skating is one of your activities, then a more frequent event to be a part of is 'Blade Night', which happens from spring to August every second Wednesday of the month. Streets in the central downtown are closed off to traffic for the evening, and rollerbladers take over the heart of the metropolis (during October to April, though, this happens indoors at Arena concert hall (Eichenstrasse 4 in Treptow).
On the other hand, if you'd also like to be out and about without wheels or crowds of any kind, then this city's many green areas,
I visited the huge Wannsee in western Berlin on a breezy but sunny late September day and lucked into the middle of a sailing regatta, while on other parts of the lake there were plenty of other craft bouncing on the waves, from paddle boats to canoes to windsurfers and jetskiers.
Berlin's better known central and western districts such as Charlottenburg, Prenzlauerberg or Mitte may still lead the way as far as best developed and numerous facilities, from indoor workouts at Gold's Gym to horseback riding to sailing and windsurfing, but you should consider at least a visit into the former East Berlin district of Koepenick, which contains a huge lake called the Moeggelsee. The shoreline along the Moeggelsee has plenty of both aquatic and land based activity, including sailing and boat rentals, windsurf and kayak rentals, and biking and rollerblade rentals; scenery and sport draw local Berliners and travelers alike from all generations, each taking advantage of the summer or fall seasons for an outing by the water.
And if you're here during the winter months, Berlin also offers some five ski slopes to practice your parallels on, and if there's been sufficient snowfall, you can hook up for lessons on the Teufelsberg, Berlin's own man-made mountain.
Olympic Stadium & Spectator Sports
Berlin's Olympia Stadion is probably one of the most famous Olympic stadium sites as the arena for the 1936 Games. Walk around inside this landmark of massive Neoclassical architecture, imagine the crowds roaring as Jesse Owens surges forward into history, and gaze at the names of all the Olympic medalists inscribed on the walls and the huge statues outside. The stadium is still very much in use, so if you check ahead you may be lucky enough to time your visit with an actual sports event.For something more recent though, you can always take part in one the more popular spectator sports that happen at various times throughout the year, from ice hockey to soccer to sailing regattas. You could try to be here during an event like the Berlin Marathon, which takes place every September -- some 27,000 runners from around the globe took part in the latest one.
With its super-efficient subway system,