We had one day to play tourist in Chicago and rode the hop-on-hop-off bus around downtown. The entire tour/loop takes about 2 hours, but there are 13 stops on the route where you can exit the bus to take in area attractions. We were able to visit the Willis (Sears) tower, Navy Pier, and Shedd Aquarium in addition to completing a full loop/tour. The last bus starts its loop at 4pm, but since most of the attractions close around 5, it works out well. The guides are friendly and knowledgable, we got do enjoy 4 different guides since we hopped off a couple of times and were picked up by a different bus at a later time. The only downfall to this tour (which is why it received 4 stars) is because it leaks BADLY in the rain. I had to move multiple times and lift my feet off the floor in order to stay dry in a fully covered bus. Many others were not as lucky and ended up wet.