marshy, forested region between Norfolk, Va., & Albemarle Sound, N.C.: c. 30 mi (48 km) long; traversed by a canal that is part of the Intracoastal Waterway
See Dismal Swamp in American Heritage Dictionary 4
or Great Dis·mal Swamp
A swampy region of southeast Virginia and northeast North Carolina. The heavily forested area has been greatly reduced by drainage. George Washington surveyed the Dismal Swamp in 1763.