U.S. Route 81 or U.S. Highway 81 (US 81) is a major north–south U.S. highway that extends for 1,220 miles (1,960 km) in the central United States and is one of the original United States Numbered Highways established in 1926 by the American Association of State Highway Officials.

The Chisholm Trail was a trail used in the post-Civil War era to drive cattle overland from ranches in Texas to Kansas railheads. The trail was established by Black Beaver, a Lenape guide and rancher, and his friend Jesse Chisholm, a Cherokee merchant. They collected and drove numerous cattle along the trail to Kansas, where they could be shipped east to achieve higher prices. The southern terminus was Red River Station, a trading post near the Red River along the northern border of Texas. The northern terminus was a trading post near Kansas City, Kansas. Chisholm owned both of these posts. In the years of the cattle drives, cowboys drove large herds from ranches across Texas to the Red River Station and then north to Kansas City.