Hidden deep inside a rural countryside is an enchanting, yet dangerous, secret known to locals as the “the gem of Texas Hill Country” — a swimming hole unlike any other.

The 140-foot deep well, featuring an opening mouth of about 12 feet, is known as Jacob’s Well and has become a prime spot for locals seeking both thrill and adventure.

But it’s also reportedly claimed several lives over the years. According to the Hays County government, swimming is allowed, but there are no lifeguards on duty. Those interested in taking the dive are cautioned that “for their own safety” they should not swim alone.

Individuals who ultimately do choose to take the plunge must first stand on a nearby ledge and stare into what appears to be a never-ending black hole beneath the surface of the water.

A viral video published in late 2012 shows several swimmers successfully taking the dive.

Others have turned to social media to virtually check-in and show off selfies documenting the experience.

The well is the result of the area’s eroded limestone and headwaters from nearby Cypress Creek.

“The extensive caving systems that are common in this region are the result of slightly acidic rainfall interacting with and eroding the limestone over millennia,” the Hays Country government says on their website. “The limestone caves and passage segments combine to form one of the longest underwater cave systems in Texas.”

“The cultural and natural heritage of Jacob’s Well has made it an integral part of the Wimberley experience. It is a beautiful place to swim, observe birds and many other kinds of wildlife, take photos, hike or have a picnic with the family,” it adds.

(H/T: Weather.com)

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