The fork of the river continues east past the Double Mountain a few miles joining with the Salt Fork of the Brazos and forming the Brazos River. The Clear Fork enters the Brazos River further east near Fort Griffin and Albany in Shackelford County.

The Brazos continues on its way past Fort Belknap to Possom Kingdom Lake, which compounds the river in the Palo Pinto Mountains. Fort Griffin (1867) and Fort Belknap (1851) were built to protect the frontier from the Comanches.

Below Possom Kingdom, the river continues through high hills and tablelands carved by the Brazos and on to Lake Granbury and Lake Whitney.

John Graves in his classic book Goodbye to a River calls this portion of the river the “upper-middle Brazos.” This small area of the American West became the cauldron for the frontier conflicts of Indians, homesteaders, cattlemen, buffalo hunters, and the U. S. Cavalry, all widely celebrated in books, movies, art, and poetry.

John Ford’s and John Wayne’s classic movie The Searchers and Larry McMurtry’s Lonesome Dove (and the miniseries with Tommy Lee Jones and Robert Duval) tell stories about the Texas frontier along the Brazos. These books and movies have defined the American Southwest in the eyes of millions of readers and viewers all over the world.