Berlin is a crazy fun city to ride your bike in. There are many bike lanes, most are on sidewalks and made of bricks or cobblestone which makes it fun. There are no hills here, but it gets windy as all get out. Oh, and most policemen here hate bikes and love giving out tickets. They have a laundry list to pick from when doing so. Tempelhof Airport just re-opened to the public so you can ride your bike on the landing strip with some old school roller-skaters. And taking a fun 30 min ride out of Berlin takes you to some pretty amazing forest areas with swimming.
Once I meet some more kids to ride with here I will take more pictures, in the mean time gaze on this: