Amazing Places

Jacob's Well Is A Dangerous Natural Wonder

When you're in Texas and it's the thick of summer, you need some cold water—stat. In Hays County, Texas (about an hour southwest of Austin) sits a popular natural swimming spot: Jacob's Well. Yes, it's refreshing and beautiful, but it's also a never-ending black hole that has lured several divers to their deaths.

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Jacob's Well in Hays County, Texas

Everything Is Bigger In Texas

If you're looking for relief from the stifling Texas heat, you'll likely be drawn to the near-constant 68°F, crystal clear water of Jacob's Well. According to the Mother Nature Network, this natural karstic spring is "fed by the Trinity Aquifer, which pushes up its water through the well and spills it into nearby Cypress Creek." It also happens to be the entrance of Texas's second longest fully-submerged cave, with plunging depths of 100 feet or more.

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Underwater exploration efforts by trained cave divers started in 2000, known as the Jacob's Well Exploration Project (JWEP). The efforts began as part of a research project with the Wimberley Valley Watershed Association, and by 2007, a full team was recruited to produce a highly-detailed map of the underwater. To date, they've documented approximately 6,000 feet of passages. So that's intense.

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The view of Jacob's Well from above

Don't Get Too Ambitious, Friends

For those of you who just want to relax and enjoy this natural wonder, feel free to safely dip your toes around the well's entrance. But if you're a daredevil—you know who you are—be warned; there have been eight fatalities between the years of 1964 and 1984. Open-water (unrestricted) divers love to explore the unforgiving depths of Jacob Well's narrow cave system, and they're often too inexperienced to handle it.

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Watch And Learn: Our Favorite Content About Caves

The Story of Jacob's Well Natural Area

Explore the story of this sacred spring of the Texas Hill Country with Wimberley Valley Watershed.

New Zealand's Glowing Blue Caves

The Waitomo Caves, located on New Zealand's north island, display glowing examples of bioluminescence.

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Key Facts In This Video

  1. The Waitomo Caves display glowing blue bioluminescent glowworms. 00:23

  2. The New Zealand fungus gnat glows a brilliant blue in its larva stage. 00:53

  3. The New Zealand fungus gnat suspends a fishing line of silk covered in mucus to catch prey. 01:48

Written by Curiosity Staff February 10, 2017