I was fortunate enough to backpack through Eurpor right after college. During the 2 months we visited about 7 countries, all just as amazing as the last. We did many amazing things and I wanted to share one with the community.
In Germany, Barcelona, Paris and Amsterdam we went on either a Mike's Bike tour or a Fat Tire Bike Tour - they were all awesome!
My buddy was just heading to Amsterdam and I told him that he had to go on the Mike's Bike tour while he was there - as soon as he got back he called me to tell me what a great recommendation it was.
I knew if he liked the advice - that I had to post it here!
The tours are done in small groups - about 15 people. You all get a beach cruiser bike (comfy and easy to ride) and an amazing tour guide.
It is an amazing way to get around and see the sites just as the locals do. The guides are full of knowledge, but at the same time are able to relate the tourists and keep everything very fun and entertaining.
You also get a great opportunity to meet other people on the tour - I still stay in touch with some people we met on our bike tours.
So if you are ever in any of these countries, you must take one of these tours (they are inexpensive as well)
Here are the sites:
Munich:
http://www.mikesbiketours.com/
Berlin, Barcelona, London, Paris:
http://www.fattirebiketoursberlin.com/tour/bike-tour/index.shtml