The nation's capital city is a mere 60 square miles (155 square kilometers), but with daily commuters coming from as far away as Delaware and West Virginia, the D.C. metro area is a monstrosity of sprawl. In fact, so many businesses and the folks who work for them have wandered outside the city limits that some have recently argued that the area's commercial center is suburban Fairfax County Virginia, rather than the District proper [source: O'Connell].
The federal city is a different animal than the other entrants on this list, given its size, lack of representation in Congress and overflow of temporary, carpet-bagging residents. One thing the District shares with the big boys, however, is big traffic. Washington metro area drivers spend an average 70 hours a year stuck stuck in congestion on the roads, some of which is likely a product of sprawl, tying the region with the Chicagoland area for most hours wasted behind the wheel due to congestion [source: Texas A&M].
The coming extension of Metro train service to Dulles Airport and beyond into Leesburg, a once quaint and quiet little town that has transformed into a booming exurb in the last two decades, is aimed at easing the pain of commuting in and around D.C., but some say it may just extend the sprawl further into the Virginia countryside [source: van Zuylen-Wood].