Find natural hot springs across America.

The United States sits on one of the great geothermal belts on earth — the Rockies, the Cascades, the Eastern Sierra, the Basin and Range — and scattered across it are thousands of places where hot mineral water simply comes out of the ground. Some have become grand resorts with a century of history. Some are a steaming pool beside a river, reached by a dirt road and a short hike. This directory maps both kinds.

What counts as a hot spring

What counts as a hot spring is wonderfully unpretentious: water heated by the earth, surfacing at temperatures warm enough to soak in. Developed springs capture that water in pools — sometimes a single historic bathhouse, sometimes a sprawling resort with two dozen pools at different temperatures. Wild springs leave it where it is: a riverside pool ringed with stones, a desert seep under cottonwoods, a mountainside tub with a view that no architect could improve.

The etiquette

The etiquette is the part nobody teaches you until you're in the water. The short version: shower before you soak, keep your head above the water, hydrate aggressively, limit soaks to 15–20 minutes, and never — ever — bring glass near a wild spring. Developed resorts have posted rules; wild springs run on the honor system, which means the honor system is you. Pack out everything, including things that biodegrade, and leave the pool cleaner than you found it.

Soaking is a bargain

On cost, soaking is one of the great bargains in American travel. Wild springs are free. Developed day-use pools typically run $15–$45 for an adult day pass, and many of the grand old resorts — the ones with a century of bathhouse history — charge less for a soak than a movie ticket costs in a big city. Private reservations, massage add-ons, and overnight lodging are where the bill grows; the water itself stays cheap.

Seasons matter

Seasons matter more than most first-timers expect. Winter is the secret season: steam rising off 104-degree water while snow falls on your shoulders is the single best argument for cold-weather travel in the West. Summer makes desert springs brutal by day and perfect at dawn. Spring runoff can flood riverside pools and close forest roads. Fall is the sweet spot almost everywhere — mild air, thin crowds, and hot water.