Radium Hot Springs sits on a bench above the Colorado River outside Kremmling, Colorado, and it looks exactly like what it is: a handful of rock pools fed by a natural spring, with no building, no ticket window, and no sign to speak of beyond a trail worn into the hillside by years of use. You reach it off Trough Road, also known as County Road 1, by parking in a gravel pullout and working your way down a short but steep path. There's no admission fee and no reservation system. What you find at the bottom is warm water, a view of the river moving past, and whoever else happens to be soaking that day, which in summer often means a raft crew that's pulled over to warm up mid-float.

This is not the Glenwood Springs or Pagosa Springs experience. There are no lounge chairs, no changing rooms, no snack bar. Radium is the other end of the hot springs spectrum in Colorado, the undeveloped end, and that's precisely the draw for a certain kind of traveler.

Why Radium Hot Springs Matters

Colorado has dozens of hot springs, and most of them have been built up over the decades into resorts with soaking pools, locker rooms, and a gate attendant. Radium Hot Springs is one of the few that's stayed close to how it was found. No one's poured concrete around the pools or run plumbing to them. The water collects in natural rock basins on the riverbank, and it stays that way because the location is remote enough, and the access rough enough, that it's never made sense to develop.

That matters most to two overlapping groups. The first is the traveler who'd rather scramble down a dirt trail than swipe a day pass at a resort desk, who wants the soak to feel like something they found rather than something they bought. The second is the rafting and fly fishing community that works this stretch of the Colorado River for a living or for fun. For them, Radium isn't really a destination at all. It's a known pull-off, a place to get the chill out of your hands after a cold morning run, marked on nobody's map but everybody's memory who's floated this section more than once.

Quick Facts

• Location: on the Colorado River near Kremmling, Colorado, reached off Trough Road (County Road 1)
• Cost: free, with no admission charge or reservation system
• Facilities: none on site, including no restrooms, changing areas, or trash service
• Access: a short, steep trail down from a roadside pullout, or by raft during the summer floating season
• Water temperature: warm rather than scalding, noticeably milder than developed hot springs resorts

Getting There

Kremmling sits in Grand County, in the stretch of Colorado between Winter Park and Steamboat Springs where the Colorado River cuts through open ranch country. From town, Trough Road runs along the river, and the pullout for the springs is unmarked in any official sense. There's no highway sign, no brown park placard pointing you in. You're looking for a gravel shoulder wide enough for a few cars, with a trail dropping down toward the water. If you're new to the area, it's worth asking locally or checking recent trip reports, since the exact pullout can be easy to miss on a first pass, especially if you're driving it after dark or in bad weather.

The alternative is to arrive by raft. This stretch of the Colorado River is floated commercially and privately through the summer, and the springs function as an informal rest stop for people already on the water. If you're booking a rafting trip in the Kremmling area, ask your outfitter whether the route passes Radium, since not all of them stop.

The Layout and Experience

There isn't much of a layout to describe, which is the point. The trail down from the pullout is short in distance but steep enough that you'll want real shoes, not flip-flops, especially if the ground is wet or you're carrying anything. At the bottom, the pools are small, a handful of rock-rimmed basins rather than one large pool, set right on the bench above the river. The water is warm, not hot, a noticeable difference from the soaking temperatures at commercial springs like Glenwood or Strawberry Park. Some visitors find it closer to a comfortably warm bath than a true hot soak, which suits a hot summer afternoon better than it might suit a freezing January morning.

There's no attendant, no posted capacity, no schedule. Whoever's there when you arrive is your company for the visit, and in peak rafting season that can mean sharing the pools with a boat crew that's pulled over for twenty minutes. Other times, especially on a weekday or in shoulder season, you might have the place to yourself.

History and Background

Natural hot springs are scattered throughout this part of Colorado, a legacy of the geothermal activity that runs along the Rocky Mountain corridor. Radium's springs were never commercially developed the way so many others in the state have been, and the reasons are mostly practical: the location is remote, the access is rough, and the pools themselves are small enough that building a resort around them was never an obvious commercial proposition. The result is a site that's persisted largely through word of mouth, passed along by rafting guides, river locals, and travelers who stumbled onto it and told a friend.

Best Time to Visit

Summer is when you're most likely to find company, since that's when rafting traffic on the Colorado River peaks and crews use the springs as a stopping point. If you want a quieter soak, an early morning visit or a trip during shoulder season, spring or fall, tends to thin the crowd considerably. Because the water runs warm rather than hot, a cool morning or a crisp fall day tends to make for a better soak than the height of a hot summer afternoon, when the water temperature can feel underwhelming against the heat of the day.

Winter access is a different question entirely. The trail down is steep even in good conditions, and ice or snow on that slope changes the calculus considerably. If you're considering a winter visit, go in with the expectation that the trail could be hazardous and plan accordingly.

Facilities and Preparation

There are no facilities at Radium Hot Springs, full stop. No restrooms, no changing area, no trash cans. That means you pack in and pack out everything, including your trash, and you plan your bathroom stop before you leave Kremmling. Bring water, since there's nowhere to refill once you're at the pullout. A towel and a dry bag for your phone and keys are worth the extra weight, given the steep scramble back up. Water shoes or sturdy sandals help both on the trail and on the rocky pool bottoms.

Because the site is unsupervised, you're responsible for your own judgment about water conditions, trail footing, and who else is around. This isn't a managed recreation site with a lifeguard or ranger checking in.

How It Compares to Similar Places

If you've soaked at Glenwood Hot Springs Pool or Pagosa Springs, Radium will feel like a different category of experience entirely. Those are resort operations, with admission fees, multiple pools at different temperatures, and full amenities. Radium has none of that. It sits closer in spirit to other undeveloped Colorado springs like Conundrum Hot Springs near Aspen, though Radium's approach is dramatically shorter, a steep few minutes rather than a multi-hour backcountry hike. The trade-off at Radium is scale and comfort for accessibility and cost: you get a short drive and a free soak, in exchange for small pools, no facilities, and a crowd you can't control.

Combining with Nearby Attractions

Kremmling is a natural base for river recreation, and a stop at Radium pairs easily with a day of rafting or fishing on the Colorado River, which this stretch is well known for among anglers chasing trout. The town itself is small and unpretentious, more a working river town than a tourist stop, which fits the general character of the springs. If you're routing through on a longer Colorado road trip between Steamboat Springs and the Winter Park or Summit County areas, Radium makes sense as a brief detour rather than an all-day destination in itself.

Practical Tips

• Wear real shoes for the trail down, not sandals, since the path is steep and can be loose underfoot
• Pack out all trash, since there's no collection service on site
• Bring your own water and use a restroom in Kremmling before you head out, as there are none at the springs
• Expect to share the pools with rafters in summer, particularly midday when float traffic is heaviest
• Check recent local reports on the exact pullout location, since there's no official signage marking the trailhead
• Go early morning or in shoulder season if you want a quieter, less crowded soak

FAQ

Is there a fee to visit Radium Hot Springs?
No. There's no admission charge and no reservation system. You park, walk down, and soak.

How hot is the water?
Warm rather than hot. It's noticeably milder than developed hot springs resorts like Glenwood or Pagosa, closer to a comfortably warm bath than a steaming soak.

Are there restrooms or changing facilities?
No. There are no facilities of any kind at the site, so plan ahead before you leave Kremmling.

Can you reach the springs by raft?
Yes, during the summer floating season the pools function as an informal stop for rafters working this stretch of the Colorado River, though not every commercial trip includes a stop there.

Is the trail difficult?
It's short but steep. Sturdy shoes are worth having, and the descent and climb back up should be factored into how much time and energy you budget for the visit.

Radium Hot Springs won't suit everyone, and it doesn't try to. There's no attendant to greet you, no locker for your things, nothing between you and the river but a worn path and whoever else made the same drive that day. For travelers chasing a polished spa afternoon, it will disappoint. For anyone who'd rather earn a soak with a steep walk and take it as they find it, free and unmarked above the Colorado River near Kremmling, it's close to exactly right.