I am not an urban geographer by design, but this city is truly an amazing feat of Urban Planning. The public transportation here is AMAZING! Get on the metro, get off at your stop, all is well with the world. (Well unless the metro hits a person, like it did while I was there this year---but it didn't affect my line...).
Well, I was in DC on business this year, but I did have a chance to scope out some of the sites, and in years past I was able to check out a few of the museums. My favorite museum of all time has to be the Museum of Natural History! It has so many different exhibits to explore and enjoy from plate tectonics to dinosaur fossils! A geographer's playground! And, the museum is free to the public!!!!!! It opened in 1910, and was actually one of the first Smithsonian buildings built to house the collections.
I'll write again about D.C., but I wanted to detail the awesomeness that is the metro and the Museum of Natural History!