The Mid-Atlantic is a traditional region of high school and college quizbowl. Its core consists of teams from the entirety of Maryland and Washington, D.C. as well as the half of Virginia east of US-29. These teams populated tournaments held in the area in the 2000s. In recent years, the proliferation of tournaments in the region has made it unnecessary for teams from DC to travel to Richmond or vice-versa on as regular a basis in order to play tournaments.
Many tournaments in the Mid-Atlantic take place along the I-95 corridor and, at least at the collegiate level, teams can often take public transit like buses or Amtrak to attend events in this region.
The extended Mid-Atlantic (from State College, PA to South Carolina) won 24 of the 27 high school national championships held from the beginning of modern high school quizbowl in 1998 through 2011; 16 of the tournaments featured two Mid-Atlantic teams facing off in the finals. As above, the post-2009 growth of good quizbowl in all areas of the East Coast has rendered it unnecessary for teams from Delaware, Pennsylvania, western Virginia, or the Carolinas to travel to DC and Richmond as often as they previously did.
The growth in nationally competitive teams from other regions has ended the Mid-Atlantic's dominance of national titles, with the 2013 HSNCT and 2013 NSC seeing no extended Mid-Atlantic team finish higher than fourth. This is widely taken as a positive sign showing that large, competitive quizbowl circuits can be created anywhere, and there is nothing inherent in a particular region or population pattern that precludes becoming successful relatively quickly. Indeed, even within the Mid-Atlantic region there is plenty of room for the growth of new teams and more teams that play non-pyramidal events like It's Academic to play more pyramidal tournaments.