 In 1958 the United States Bureau of Reclamation took advantage of this natural feature to construct the Flaming Gorge Dam, creating the Flaming Gorge Reservoir, which began filling in 1964.The county terrain slopes to the north and east on the northern flank of the Uintas.The county's highest point is on a mountain crest along its south border, at 12,276' (3742m) ASL.