Mass ave.........is the longest..............where the embassies are..............well, a good amount of them......



Washington's longest avenue, Massachusetts Avenue, runs parallel to Pennsylvania (a few avenues north). Along the way, you'll find Union Station and then Dupont Circle, which is central to the area known as Embassy Row. Farther out are the Naval Observatory (the vice president's residence is on the premises), Washington National Cathedral, American University, and, eventually, Maryland.