This was a fantastic tour. Tim is a great host-he has an obvious love for this city and it's attractions. I've been to DC before, yet I learned a ton of things that I had never known before. We were a huge group-it was Easter weekend, the beginning of the Cherry Blossoms and the first nice day in a while-but Tim took it on, undaunted. He warned us it would be a long tour-the website says the same. With the tidal basin, it was almost 6 hours, but I think part of that was due to the size of our group and the number of visitors to the DC area. I would highly, highly recommend.