I went to Dordrecht for just a short time, a very small town. We made a mistake on the waterbus that led us to walking around the town for a few hours until we could get to the intended goal of Kinderdijk. Kinderdijk is the home of the famous windmills that Holland is known for. The windmills are preserved and still working but not used since the invention of the electric pump.
After spending a few days in Amsterdam, it was very refreshing to goto Rotterdam. Rotterdam, a 1h20m train ride away from Amsterdam, was interesting to me because it is essentially a new town by Europe standards. There are many, many new buildings in Rotterdam since it was bombed and essentially destroyed during WW2, however, being the largest port in Europe (formally the largest in the world) it has been rebuilt pretty fast.
I was in Amsterdam for 3 days and 2 nights. My first impressions were quite interesting. The culture in Amsterdam is quite liberal and relaxed, but it is also regulated. This was my first stop in my RTW trip. As my first stop, it was a great place to be dropped in to Europe. It allowed me to get into the Euro mindset and figure out what the heck I was doing.