Just outside Austin, Texas, in a small town called Wimberley is an everlasting spring that has captivated thrill seekers for years. Upon first glance, Jacob’s Well doesn’t seem all that special, but take a closer look and it's mysteries will soon be unveiled. After you cross the footbridge and round the stones lining the edge of the swimming hole, you’ll notice the bubbling turquoise waters change to a dark, sapphire hue the deeper the water gets. Its mysterious depths have become an Instagram-must for Austin visitors, spurring a wave a travelers from all over the US in the process.

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Appearances Can Be Deceiving

On the surface, Jacob’s Well is like any other swimming hole in Texas: The water temperature hovers around a near-perfect 68-degrees year-round, while various aquatic animals can be seen sunning themselves on the rocks or swimming in the shallows. The actual Well is a 30-foot vertical drop that seems to go straight down to the middle of the earth. Fed from a nearby spring, you can see the bubbles overflowing into a nearby creek that's just shallow enough for families to find some sweet relief from the sweltering Texas heat. Most visitors to Jacob’s Well don’t even know there’s an entire cave complex beneath them.

Below the Surface

Jacob’s Well extends into a series of caverns that stretch for nearly a mile, making it the longest underwater cave system in Texas. The twisted caverns, tight crevices, and dark, sometimes foggy conditions, can be dangerous, even for experienced SCUBA enthusiasts. Only professional divers with the Jacob’s Well Exploration Project can dive the site, and even they call it a “challenging, unforgiving environment.” Through their research efforts, they’ve charted nearly 140-foot depths, more than a mile of caverns, and, most recently, a fourth chamber that has been described as a virgin cave.

Mysteries and Secrets

Key to Jacob’s Well’s allure is the abnormality of it all. According to Texas Parks & Wildlife, more than half of the springs in the Lone Star State have dried up since 1900 — except Jacob’s Well. Native Americans, Spanish explorers, and early pioneers have all documented the Well in their travels, seeing it as a place of hope and renewal, while local tribes consider the land sacred.

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The History

How Jacob’s Well got its name is still a bit of mystery. Local settlers are said to have discovered the area in the 1850s, but that glosses over a few key facts including its christening. The truth is the name “Jacob’s Well” was probably around more than 20 years before that. Locals say a survivor of the Texas Revolution (way back in the late 1830s) likened the area “unto a well in Biblical times.”

How to Do It

Jacob’s Well Natural Area opens the swimming hole to visitors around Memorial Day weekend. While there is no fee for hikers who want to check out the trails, there is a small one for swimmers. In order to keep the area preserved for future generations, swimmers are also required to book a reservation, which is unlike many other outdoor pools. We think it’s worth the pre-planning though. Maybe you’ll even be able to help unravel the secrets of the mysterious waters.