The North Fork Red River, sometimes called simply the "North Fork", is a tributary of the Red River of the South about 271 mi (436 km) long, heading along the eastern Caprock Escarpment of the Llano Estacado about 11.4 mi (18.3 km) southwest of Pampa, Texas.

[3][4] Rising in Gray County, Texas, it terminates at the confluence with Prairie Dog Town Fork of the Red River at the Texas-Oklahoma border.

[5] It joins the Prairie Dog Town Fork of the Red River at the Texas-Oklahoma border about 12.7 mi (20.4 km) northeast of Vernon, Texas.

[6] Overall, the North Fork descends 2,098 ft (639 m) from its headwaters to its confluence with the Red River, passing through mostly rolling to flat terrain with local shallow depressions along its course.

The U. S. government thereafter claimed the land between the two Red River streams as far as the 100th Meridian as part of its own territory.