WELLSVILLE, Colo. — Technically speaking, there is no such place as Rincon, Colo.

The name, derived from the Spanish word for “angle” or “corner,” doubles as the location of a boat ramp on the Arkansas River maybe 10 miles east of Salida, but to members of the local “squirt boating” subculture who gathered on a recent weekend for the inaugural Rincon Rendezvous, it will always be known as a place of mystery.

And that’s just how they like it.

“From what I’ve heard, it used to be called ‘Squirt Dome’ back in the day,” said Lenny Eckstein of Golden, Colo. “But it seemed like squirt boating kind of phased out around here for a while, until some guys kind of brought it back in the past couple years. So now we’re thinking about giving it a new name.”

For the moment, however, Rincon works just fine.

In geological terms, it represents a small, secluded valley, a hollow recess or bend in a stream, what might be called a nook. In kayaking terms, it represents a niche.

Squirt boating, Eckstein’s preferred form of kayaking, is an offshoot of the sport using boats designed with as little volume as possible. East Coast kayaker Jim Snyder is considered the godfather of the discipline, crafting the first squirt boats after seeing the low-volume sterns of slalom race kayaks slice beneath the river’s surface on sharp turns, then use the trapped buoyancy to shoot forward like a watermelon seed squeezed between your thumb and finger. Snyder took the move a step farther by shrinking the bow of the kayaks.

Where the volume of a modern whitewater kayak might range between 50 and 70 gallons, squirt boats are typically less than half that, leaving 80 percent to 90 percent of the kayak below the surface of the river at any given moment. The idea is that the low-volume kayaks can make use of surface and underwater currents to perform tricks that are impossible in other vessels. Among them is the trick of choice at Rincon, the “mystery move.”

“This is about as good as it gets in my book,” Eckstein said of the otherwise innocuous site. “Especially in terms of mystery spots.”

Considered the Holy Grail of squirt boating tricks, the mystery move is somewhat counterintuitive to most “surface boaters.” Rather than paddling over waves and around obstacles, the mystery move is about getting a kayak as deep underwater as possible, submerging your boat and yourself in the flow of the river. The more “down time” a paddler achieves, the higher his status in the squirt world.

True to its name, it is the nooks and bends of the river that create the optimal conditions at Rincon. A small island channels the river into two separate braids that form a fluid corkscrew when they converge again downstream. By entering the downstream seam at the appropriate angle — what Snyder has dubbed the “charging arc” or “charc” — squirters can ride the downward flow of the whirlpool and remain suspended as deep as 10 feet underwater for lengthy periods.

For many outside of the sport, however, the question is, why?

“That’s the million-dollar question,” said Sam Bass of Boulder, a 15-year squirt-boater. “We always have such a hard time answering. But once you get down and get your head underwater, it’s like being on a different planet. It’s a totally different set of rules.”

Like many attracted to the discipline, Bass, 30, finds himself tuned into some combination of the abstract and the intricate that leaves him feeling “more engaged” with the river than in traditional boating. He likens it to an alpine skier making the conversion to telemarking, just to keep things interesting.

Miles Gallagher, a five-year squirt-boater from Estes Park, Colo., goes so far as to wear an aerodynamic time trial-style bicycle racing helmet and scuba mask while squirting, but only loose-fitting neoprene so he can better feel the river currents flowing against his body while underwater.

“A lot of people think it’s cool, but a lot of people think we’re nuts. They just don’t understand,” said Eckstein, 32. “But everybody’s got their thing, and once you find yours it’s understandable.”

Foul weather, cool temperatures and low river flows on a recent Saturday kept the numbers down to about 10 squirters at Rincon, maybe a third of Eckstein’s estimate of the statewide community. The handful that remained the next day, however, were rewarded with optimal flows under sunny skies, a hot commodity in water temperatures hovering at about 55 degrees.

The boaters took turns slicing shimmering fiberglass kayaks through the confluence, some using paddles and others only their hands, swirling into the murky currents and disappearing into an aquatic underworld for up to 20 seconds before re-emerging downstream. There were no judges, no competition, no audience — only a small group of friends immersed in the aesthetic mystery of the moment.

“There’s no competition, but I think everyone here is pushing themselves,” Gallagher said. “I know I am. I’m just trying to be as fluid as possible.”