Iron Mountain’s Adults-Only Hot Springs Take You Around The World

For 10 minutes on a Thursday morning, I’m bathing in the warmth of the Osaek Hot Springs in South Korea. The iron- and manganese-rich waters soothe my muscles, which are still exhausted from a long hike earlier in the week. I pop out of the pool into the crisp air, take a few steps, and land in Iceland’s Blue Lagoon.

No, I’m not teleporting—I’m hopping between the 10 “world experience” pools at Upriver, a new, 21-plus section at Iron Mountain Hot Springs in Glenwood Springs. Each pergola-covered pool is a replica of a well-known global hot spring—in terms of the mineral formulas, not appearance. The healing waters of Kirsehir, Turkey, are rich in bicarbonate, sulfate, and calcium, for example, while Bali’s Banjar Hot Springs lean more toward sulfate and magnesium.

“We spent the last two to three years perfecting those recipes so they’re the exact compositions of some of the most famous hot springs in the world,” says Iron Mountain owner Steve Beckley, who’s also behind the Glenwood Caverns Adventure Park.

Beckley has around two dozen hot spring recipes, so the lineup of countries will rotate throughout the year giving soakers a chance to visit new places. They can also lounge in the pebble-bottomed pool they’ll get the most out of; signage explains the pools’ respective ingredients and which health issues (muscle pain, inflammation, sleep) they potentially aid.

When Iron Mountain opened in 2015, it was intended to be a counterpoint to the massive, boisterous Glenwood Hot Springs Resort—with its lap lanes, splash zone, and lazy river ride—down the road. The Colorado River–adjacent venue further leans into that identity with the adults-only Upriver, which opened in July. You need a special wristband to access the tranquil space, which also includes two larger freshwater pools, a cold plunge pool, and the Sandbar Cafe, which serves cocktails, beer, and a relatively healthy menu of smoothies, salads, and shareable plates.

I managed less than one minute in the cold plunge’s arctic waters before I had to pull myself out to be enveloped in the welcoming heat of Australia’s Yarrangobilly Hot Springs. Cold water therapy, or moving between chilly dips and hot soaks, is trending in wellness circles these days, something Beckley is well aware of. He plans to add a second, larger cold plunge next year. (A barrel sauna, outdoor lockers, and additional eating areas and cabanas are coming in 2024, too.) But if the cold plunge isn’t your thing, there are plenty of other options. I think I’ll stick with visiting the countries I haven’t yet crossed off my Upriver passport on my next visit.

If You Go: Upriver tickets start at $46, are valid for three hours, and include two towel rentals and access to the full Iron Mountain property. Staying overnight? The historic Hotel Colorado, which recently updated its guest rooms, sits just a mile away.