Amy:
I just came back from a wonderful trip to Berlin. A very significant observation of mine is that the Germans love their bike-riding. Bikes are all over and widely accepted. I even think you can take bikes on all the transportations systems. Some of the train cars are even marked with the bike symbol.
There are many, many beautiful areas to bike around. There are many bikes paths. Some are marked in the road, and some are marked on the sidewalks by different colored or shaped pavement.
I believe all of the five-starred hotels that I stayed in would have arranged a rental bike for me. One of them had a stack of bikes outside -- maybe a group was renting them. I think my hotel said they are 25 Euros per day, but I think I saw signs on bikes for a much lower cost; i.e., 15 Euros.
On a recent holiday, there was a respectable couple with two small children on an U-bahn. They were heading for a day of biking.
You could bike around all the tourist sites, and many of the palaces/schlosses have extended and beautiful grounds to bike around. i.e., the Charlottenburg Palace. In addition to Museum Island, you could bike around the Tiergarten/Reichstag,
Strasse de 17 Juni is beautiful (extended from the Brandenburg Gate).
I will say I did not see any of those extended "trail a bikes" being used. They could be cumbersome. I think for the couple I did see, that the small child (age5/6/7), he rode his own. For the little one (maybe 2), there was a child's seat that was attached to the back of the bike.
You did not mention the age of your children. Do enjoy biking. I think you would love it.
