Climb to the top of Teufelsberg and you'll be rewarded with glorious views. Try to visit at sundown or sunrise for an even more memorable experience.
You're spoiled for sightseeing choice when in Charlottenburg-Wilmersdorf. Teufelsberg is a good place to start here, but there are loads of other worthy places to explore. Brandenburg Gate, Reichstag Building, and Potsdamer Platz are near the naturally raised area of land and will top off your day nicely.