Three of us piled into a car, found the well-marked gravel road and began our plunge down a couple of roller coaster miles along steep ravines to our destination.

Devil’s Well is the largest known natural underground lake in Missouri. Through a hole no wider than a backyard trampoline it beckoned us to peek a hundred feet straight down into an underground river. One of the area’s preeminent geologist-explorers calls it a big stomach. It’s Mother Nature’s perfect indoor pool, except that it’s cold and dark and underground and scary as hell, hence the name.

Before the Devil relinquished this well to the National Park Service, a few lucky folks descended into the stomach, er, sinkhole in a bosun’s chair. It was a ride much like the worm experiences when dangled from a fish hook, although the conclusion is less digestive.

Back then, the actual owner was Bill Wallace. He and his brother first explored the cavern in 1954, via that bosun’s chair.

Excited about our hot afternoon journey, we parked in the Devil’s Well parking lot and walked the steep switchback trail down into the well. The sinkhole’s dimensions are such that it would make a perfect sheath for a small tornado...if Satan wanted to store one here. The hole narrows to the size of an inverted forest tower, descending to a platform where we peered over a ledge through a hole that could easily become plugged by an elephant if it fell from the sky into this vortex. Ten stories beneath our peephole was the water. The cavern is the exact size and circumference of the Astrodome, best I can tell. So this hole is the world’s first domed sports facility.

Divers, cavers and mappers joined together in a project called Ozark Spring Studies to explore this well over 62 weekends from 1969 to 1973. Dye tracing indicates this underground river surfaces at Cave Spring on the Current River.

The National Park Service bought the land in 1974.

Today, you can’t ride the bosun’s chair into the cavern, but thanks to well-hung electric lights, we saw the cavern and its pool, which would be the eighth wonder of the world except that it already has a higher ranking as the seventh wonder of Shannon County.

We ascended the staircase out of the hole with the realization that the surrounding terra was not that firma. That was our first unsettling revelation.

Our second unsettling revelation came when our driver tried to start her car. Dead battery. Middle of nowhere. No cell phone service, and a gravel road that switchbacked up a steep hill for two miles to the nearest country blacktop. So I started running up the gravel road to find help.

Up the hill, closer to the fringes of the outer beginnings of the path to the edge of civilization, I met a van carrying a vacationing family from Wisconsin descending into the valley that contains the hole that leads to the Seventh Wonder of Shannon County. Friendly and willing, they provided the jumper cables and the juice to start the car and get us out of the vortex of the Devil.

That evening, over homestyle fried chicken at a country cafe called Jason’s Place, among friends whose jobs it is to set tourism lures, we relayed the story of surprise and despair and the kindness of strangers, all within the clutches of the Devil and his well.

John made it home. Erifnus is fine. See more at JohnDrakeRobinson.com/blog. His books, Coastal Missouri and A Road Trip Into America’s Hidden Heart are available at independent bookstores and online booksellers everywhere.