Marathon's name was suggested by a sea captain who said the area reminded him of Marathon, Greece. A cattle and mining shipment center in its heyday, the town on U.S. 90 at the junction with U.S. 385 is a tourist crossroads, a major gateway to Big Bend National Park and a headquarters for vast ranching activities. Visitors can catch glimpses of the town's colorful past at the Marathon Museum, at North Third Street and Avenue E, and the old Marathon Jail at South Second Street and Avenue C. The town hosts West Fest, complete with a cabrito cook-off, in September, and the Fiesta de la Noche Buena takes place in early December.

The Great Marathon Basin area is noted for extensive surface outcroppings of varied rocks and minerals, popular with professional geologists and amateur rockhounds.