Stand up paddle boarding with Charlie MacArthur from the Aspen Kayak Acadamy. Showing how it's done. (Cameron Martindell/CAMERON MARTINDELL)

I watched in awe as the surfer zigged skilfully across the crest of the powerful white-capped wave, maintaining his balance even as it lifted and dropped him with hurricane-like force. Behind him, on the shore, a line of surfers, boogie boarders and stand-up paddle boarders eagerly awaited their turn at conquering the wave.

Don’t think that we were at some vast beach in Hawaii, though. The nearest ocean was about 1,000 miles away.

This surfer haven is in Glenwood Springs, Colo., at a $1.4 million white-water park along the Colorado River, where engineers have placed structures in the water to create perfect surfing waves.

River surfing was just one of the surprises Colorado held for me on a recent trip. I’d never thought of this state so famous for its premier skiing venues as a summertime water sports destination. But my experience around Glenwood Springs, Aspen, Carbondale and Snowmass showed me that on that score, I was all wet.

The area is crisscrossed with rivers — the Colorado, the Roaring Fork, the Frying Pan and the Crystal. I found a gorgeous lake for swimming and sailing. I zip-lined 1,400 yards across the Colorado, rode a raft through hair-raising rapids, kayaked, soaked in hot springs, learned to fly fish and to stand-up paddle board.

And all these water adventures are underscored by breathtaking views of granite cliffs and snowcapped mountains beneath vast blue skies. Beyond the scenery, there are the art and music festivals that bring big-city culture to this basically rural area, and restaurants that attract great chefs from around the country.

It’s no mystery why lots of people who could live anywhere choose to settle in this region — people like Lance Armstrong, Jack Nicholson, Melanie Griffith, Kurt Russell and Goldie Hawn. Hunter Thompson had a home near Aspen, and when he died, Johnny Depp threw him a wake rumored to cost $3 million — a price tag that included shooting Thompson’s ashes into the sky from a cannon.

After the flight from Washington to Aspen, I decided that a hot mineral spring soak would be the perfect antidote to cramped airline seats. Within a short time, I found myself in a natural geothermic pool along the Crystal River. Penny Hot Springs is a 20-foot-wide area, sectioned off by rocks and surrounded by high granite cliffs, that captures hot spring waters flowing into the river before they can mingle too much with the cold river water.

Later in the trip, I lounged in what is claimed to be the world’s largest hot springs pools. The two pools at Glenwood Hot Springs — one kept at just over 90 degrees and the other at 104 degrees — cover an area more than two city blocks long. You can also buy a day pass to an athletic club within the pool complex, featuring a full-service spa, exercise equipment, a steam room, a sauna and handball and racquetball courts.

One of the highlights of my vacation was a white-water rafting trip on the Upper Roaring Fork River in Snowmass. It was July, but the extremely heavy snowfalls of the winter were still melting and swelling the rivers with well above average white water. Wet suits, provided by our outfitter, Blazing Adventures, were a must. As our guide, Michael Glock, explained, “The water we’re riding today was snow yesterday.”

As we made our way down the river, adrenaline-stoking crashes through rapids alternated with leisurely stretches when we floated languidly past woods and upscale waterfront homes, including one owned until recently by Ringo Starr. Despite these more slow-moving parts, the 12-mile trip, which often takes two hours, was over in an hour, due to the river’s swollen state.

The same phenomenon prevented fly-fishing on local rivers, so instead I took some lessons from an expert guide on a Carbondale pond stocked with trout. Apparently I’d missed some of the best fishing in the world by about a week, as the late snow melt had stirred up the rivers so much that fish couldn’t see well enough to feed. Soon, however, the rivers would clear and the starving fish would be hitting as many lures as a fisherman could cast, declared my guide.

And then there are the lakes. Maroon Lake, near Snowmass, lies in a crater carved by Ice Age glaciers. The clear water reflects two snow-capped peaks. This is supposedly the most photographed spot in Colorado. Local outfitters provide my kind of mountain biking: They drive you up the mountain to the lake and give you a bike to ride back down. Other nearby bodies of water worth a visit are Carter Lake and Ruedi Reservoir.

The biggest attraction for expert surfers, kayakers and upright paddle boarders are the man-made river waves. But since I only have minimal surfing experience, Glenwood White Water Park was way beyond my abilities. When I decided to try some stand-up paddle boarding, or SUP, I headed for calm waters and the expert guidance of Charlie MacArthur, a leading surfer and SUPer.

MacArthur started surfing at age 7, when his father settled in Oahu to play the role of Danno on the original “Hawaii Five-O.” Soon after the rise in popularity of SUP in Hawaii, MacArthur adapted the sport to river waves, became a premier expert and opened a kayaking and SUP school in Aspen.

In the river, unlike in the ocean, the wave is a standing wave, and the surfer travels diagonally across the crest. You travel faster on ocean waves, but you get more action on the river, according to MacArthur. “You don’t have to wait for the right wave,” he says. “The wave is there all day. During a two-hour session in the ocean you’re surfing maybe five minutes. Here, you can get a new ride every three minutes.”

The park and others like it are, says MacArthur, “bringing the Aloha feeling to the mountains. It’s a real surfer vibe.”

Yes it is. In fact, my summer trip suggested a new motto for the nation’s eighth-largest state: Colorado, the all-season destination.

Loose, a former Travel staff writer, is a freelance writer and editor in Washington.

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