The National Road was the first major improved highway in the United States built by the federal government. Built between 1811 and 1837, the 620-mile (1,000 km) road connected the Potomac and Ohio Rivers and was a main transport path to the West for thousands of settlers. When improved in the 1830s, it became the second U.S. road surfaced with the macadam process pioneered by Scotsman John Loudon McAdam.

The Ohio River is a 981-mile-long (1,579 km) river in the United States. It is located at the boundary of the Midwestern and Southern United States, flowing in a southwesterly direction from western Pennsylvania to its mouth on the Mississippi River at the southern tip of Illinois. It is the third largest river by discharge volume in the United States and the largest tributary by volume of the north-south flowing Mississippi River, which divides the eastern from western United States. It is also the 6th oldest river on the North American continent. The river flows through or along the border of six states, and its drainage basin includes parts of 14 states. Through its largest tributary, the Tennessee River, the basin includes several states of the southeastern U.S. It is the source of drinking water for five million people.