Despite the highfalutin resonance of its classical-sounding name, Thermopolis (pop. 2,974) is a sleepy little retirement town, surrounded by red-rock canyons and centered among a remarkable set of natural hot springs. The land was bought in 1896 from local Shoshone chief Washakie and Arapaho chief Sharp Nose on the understanding that the spring waters be kept open to the public, indigenous and newcomer alike. This spring, which flows at a rate of 18,000 gallons of 135°F water daily, was the basis of Wyoming’s first state park, Hot Springs State Park (538 N. Park St., 307/864-2176, daily, free), which still covers the east bank of the Bighorn River. A state-run bathhouse has showers and changing rooms—you can rent towels and bathing suits for a nominal charge. There are two commercial enterprises in the park—Hellie’s Tepee Pools and Star Plunge—with water slides, saunas, and so on, perfect for families with littler kids.

Across the river in the center of town, the enjoyable Hot Springs County Historical Museum and Cultural Center (700 Broadway St., 307/864-5183, Mon.-Sat. summer, Tues.-Sat. winter, $5) has a wide-ranging collection of historic photos, farming and oil-drilling implements, and even the cherrywood bar from the Hole-in-the-Wall Saloon where Butch and Sundance supposedly bellied up for a drink or two. The final big draw in Thermopolis—and I mean big—is the Wyoming Dinosaur Center (110 Carter Ranch Rd., 307/864-2997, daily, $10), on the east side of town. Wyoming is one of the world’s most abundant sources of fossils. Follow the green dinosaur footprints from the center of town to a paleontology dig that’s open to the public. Finds on display include a full T. rex and a triceratops.

The friendly Thermopolis visitors center (220 Park St., 877/864-3192) has more information on the area, including details about the intriguing Legend Rock petroglyphs north of town.