Flat Top Mountain is a broad ridge in southern West Virginia within the Allegheny Mountains, distinguished by an elevated, unusually level crest rather than a single peak. Its highest point is Huff Knob near the community of Flat Top, and its tableland of Guyandotte sandstone gives the mountain its name. The ridge forms a local boundary between the Allegheny Plateau and the Ridge-and-Valley Appalachians, with land dropping steeply toward the Bluestone River valley and more gradually northwest toward streams flowing to the Kanawha and Ohio rivers. Beneath parts of it lies the Pocahontas Coalfield, while livestock, Christmas tree farming, recreation, and rail transport have also shaped its history and use.