Map of Thermopolis town

Thermopolis is the county seat and largest town in Hot Springs County, Wyoming, United States. As of the 2020 U.S. Census, the town population was 2,725.

Thermopolis is Greek for “hot city.” It is home to numerous natural hot springs, in which mineral-laden waters are heated by geothermal processes. The town is named for the hot springs located there.

The town claims the world’s largest mineral hot spring, appropriately named “The Big Spring”, as part of Hot Springs State Park. The springs are open to the public for free as part of an 1896 treaty signed with the Shoshone and Arapaho Indian tribes.

Dinosaur fossils were found on the Warm Springs Ranch in 1993, and the Wyoming Dinosaur Center was founded soon after.

Thermopolis town overview:
Name:	Thermopolis town
LSAD Code:	43
LSAD Description:	town (suffix)
State:	Wyoming
County:	Hot Springs County
Elevation:	4,331 ft (1,320 m)
Total Area:	2.47 sq mi (6.39 km²)
Land Area:	2.39 sq mi (6.18 km²)
Water Area:	0.08 sq mi (0.21 km²)
Total Population:	2,725
Population Density:	1,157.94/sq mi (447.11/km²)
ZIP code:	82443
Area code:	307
FIPS code:	5676515
Website:	www.townofthermopolis.com

Online Interactive Map

Click on to view map in "full screen" mode.

Thermopolis online map. Source: Basemap layers from Google Map, Open Street Map (OSM), Arcgisonline, Wmflabs. Boundary Data from Database of Global Administrative Areas.

Thermopolis location map. Where is Thermopolis town?

Thermopolis location on the U.S. Map. Where is Thermopolis town. — Thermopolis location on the U.S. Map.

Thermopolis location on the Wyoming map. Where is Thermopolis town. — Location of Thermopolis in Wyoming.

Thermopolis Road Map

Thermopolis city Satellite Map

Geography

Thermopolis is located near the northern end of the Wind River Canyon and Wedding of the Waters, where the north-flowing Wind River becomes the Bighorn River. It is an unusual instance of a river changing names at a point other than a confluence of two streams. The dual name is ascribed to the mountain barrier between the Wind River and Bighorn basins, obscuring the fact that the river that drains the two is the same. The term “Wedding of the Waters” dates to at least 1934, when a marker was placed at the location.

Thermopolis is ringed by mountains, with the Big Horn Mountains to the northeast, the Bridger Mountains to the southeast, the Owl Creek Mountains to the southwest and the Absaroka Range to the northwest. Thermopolis is the southernmost municipality in the Big Horn Basin.

Roundtop Mountain, on the northern edge of town, is a unique geological formation shaped much like a volcano. It sits at approximately 6,000 feet (1,800 m) and is the highest area in the immediate vicinity of Thermopolis.

A large body of water, Boysen Reservoir, lies approximately 17 miles (27 km) south of Thermopolis and is inhabited by many species of fish including rainbow trout, cutthroat trout, brown trout, walleye, northern pike and perch among others.

According to the United States Census Bureau, the town has a total area of 2.47 square miles (6.40 km), of which 2.38 square miles (6.16 km) is land and 0.09 square miles (0.23 km) is water.

Climate

According to the Köppen Climate Classification system, Thermopolis has a cool semi-arid climate, abbreviated BSk on climate maps. The hottest temperature recorded in Thermopolis was 107 °F (42 °C) on July 25, 1929, while the coldest temperature recorded was −44 °F (−42 °C) on January 16, 1930.