There are six hypergraphic links on this map.

marillo, Texas, has been included on this map merely as a reference point. It was founded in 1887 as a railroad construction camp, and grew to be a center of ranching, wheat farming, and oil drilling. It is on the low divide that separates the Red River drainage from the Canadian River drainage in the Texas panhandle.

Chihuahua, the present capital of the Mexican State of Chihuahua, was originally settled in the 16th century, and "officially" founded in 1709. At the end of the 18th century it was a commercial center on the 1,600-mile Camino Real ("Royal Road") that connected Mexico City with Santa Fe.