English Heritage's list of Scheduled Monuments describes this as a bowl barrow, though other sources call it a long barrow. A long boundary mound (with 'possible prehistoric origins') lies adjacent.
Dunseal longbarrow is intact and unexcavated, it stands 175m above sea level,and measures about 27m x 14m and 2m tall.
The barrow marks the eastern extent of neolithic activity and the south eastern extent of the Black mountains group .
Date of construction is unknown but its position on a narrow ridge with panoramic views is suggestive of late neolithic/early bronze age.