Continental Divide watersheds of North America center on a dramatic mountain range that parts the West & East watersheds in a sharp north-south line. It is also a formidable physical barrier, or divide. Furthermore, the mountains that form this line rise sharply from the prairie lands that occupy the center of the continent. Approached from the flat prairies during exploration, the mountains looked like a wall on the horizon, so the divide was very conspicuous.
In the pioneer days of the United States, transportation to the West Coast was via ship, which sailed almost to Antarctica, to round the southern cape of South America. It was an extremely circuitous way to get across the country, with danger and expense adding injury to insult.