Bottomless Pits

Bottomless Pits

We post holes here, sir.

Sinkholes, pit caves, wells and cenotes all have one thing in common; sometimes they’re bottomless. Not truly “bottomless”, of course, but in appearance, reputation, or of incredible depth. We’ve seen a few of these “bottomless pits” in prior lists such as the Lost Sea in Tennessee or the Devil’s Hole in Nevada, but today we will focus on those strange places in the earth that seem to be endless.

1. Laguna Kaan Luum, Mexico

This one threw me for a loop because I was originally only seeing pictures like the one above, so I was like ‘oh, that’s cool, so it’s kinda like Dean’s Blue Hole, where it’s an ocean sinkhole right off the shore…’

No. It’s not that. Let’s zoom out a bit.

Yeah. This is a lake with one giant sinkhole in the middle! It’s about 2,000 feet across and reaches depths of 278 feet, with the surrounding shallows a very pleasant 4 feet deep! I’m mostly including it on the list because the full image hit me like a bus.

2. Sima Humboldt, Venezuela

Tepuis are large plateau mountains found across Venezuela, often with sheer sides and inaccessible tops that inspired explorers to imagine dinosaurs still surviving on these isolated mesas. Even on their own, tepuis are incredible, beautiful and mysterious. Add a sinkhole with an even more isolated forest at the bottom, and you have all the ingredients for some crazy shit to happen. Sima Humboldt and Sima Martel are two enormous sinkholes at the top of Cerro Sarisariñama. Humboldt is the largest at over a thousand feet across and nearly the same in depth, with a jungle flourishing at the bottom. The sinkhole forests are home to many endemic species of both plant and animals, but so far, no prehistoric monsters have been found in any of them.

3. Well of Barhout, Yemen

The “well of hell” is a massive sinkhole in the desert, measuring about 100 feet in diameter and plunging down over 300 feet. Understandably, there are many myths and legends about this place, including a story about an evil djinn which lives at the bottom and takes the head of anyone foolish enough to climb in. In fact, so pervasive are these legends that the sinkhole was only formally explored in 2021! Luckily they did not find any evil spirits, but they did find stalagmites which reached 30 feet tall, cave pearls, and waterfalls which provided refuge for frogs and snakes.

4. Myakka sinkhole, Florida

This murky abyss is filled with more than just water, it is also home to over a hundred alligators. Due to the poor visibility and very high concentration of large carnivores, it is very difficult to study this pit. Only a few people have ever glimpsed the bottom of this 134-foot deep sinkhole, but apparently we aren’t missing much because the water down there is stagnant and inhospitable to most life. Exactly why this area is so popular among alligators is still unknown, but it’s likely due to a combination of food availability and ideal temperatures.

5. The Pit cenote, Mexico

Like Cenote Angelita, The Pit is a layered cenote. The first 88 feet is freshwater, then there is a “fog” of hydrogen sulfide, below which lies over 300 feet of brackish water. The Pit is a spectacular-looking cenote, with an almost otherworldly quality, which makes it very popular among divers. So far, this pit has been explored to a depth of 390 feet, but unexplored passages extend further.

6. Thor’s well, Oregon

Like a drainpipe continuously swallowing an unbroken stream of ocean water, Thor’s well is often likened to a bottomless pit. However, it is actually only about 20 feet deep, and the drain effect is due to the fact that it connects back to the ocean, not swallowing the water but simply rerouting it. This does not mean that there is no danger, though. The rocks are slippery and sharp, and this area sees a higher than average number of ‘sneaker waves’; waves that look normal as they roll in but are actually much larger than they appear, potentially sweeping people out to sea as they retreat. The true danger here is the ocean, not the well.

7. Vouliagmeni Lake, Greece

This incredibly beautiful saltwater lake has been rumored to have healing properties for thousands of years, and today continues to draw in visitors for its medicinal minerals and “doctor fish”. But this famous lake hides a secret; a labyrinth of caves whose depths have never been fully explored, and whose connection to the ocean remains undiscovered. Passages stretch over a mile into the mountains, with an average depth of 260 feet. The largest of these caverns is nearly 500 feet wide and full of warm sea water. Although a spectacular diving spot, these unknown caverns are best not underestimated.

8. Santa Rosa blue hole, New Mexico

A gorgeous natural swimming hole, this cenote is roughly 80 feet wide and 80 feet deep (in most places) and is a popular destination for tourists. It was also used for diving certification tests, until an incident in 1976. There is one spot in this picturesque cenote that goes down much further than 80 feet; the entrance to a cave. In the dark, twisting passages, two young divers got lost and died, and the cave was later sealed with a metal grate to prevent other divers from attempting to enter. The cave was mostly forgotten about until 2013, when cave divers were given permission to attempt to map the area. The blue hole is at least 200 feet deep, but the bottom of the cave still has not been found.

9. Roaring River Spring, Missouri

This turquoise river bubbles up from a ten-foot wide pool of deep water hidden within a sheer-sided canyon. But despite its peaceful appearance, this spring discharges 20 million gallons of water a day, and the exact source is still unknown. In 1979, divers attempted to map the cave, but reached a point 225 feet down where the passage constricted and had a water flow like “the force of an open fire hydrant”, preventing them from going any further. In 2020, divers waited until the water flow was lowest in the summer and descended to a depth of 472 feet with no bottom in sight, making this the deepest spring in the US!

10. Your Mom.

I jest, of course. Here’s the real one:

Hranice Abyss, Czech Republic

A tiny greenish lake in the forest is the opening to the deepest freshwater cave in the world, deeper than the Empire State Building is high and still seemingly bottomless. It is so deep that scientists think it may have been formed by a totally different process than most freshwater caves; instead of water eroding away the ground from above, it may have been created by acidic groundwater coming up from below. And this water is extremely acidic, able to burn a diver’s skin if not covered properly. This, combined with fallen trees and other debris, poor visibility, and the sheer vertical drop of the cave, creates incredibly dangerous conditions for diving. Because of this, no diver or ROV has reached the bottom yet. But with a recent study using seismic sensors, scientists have estimated that the abyss may be over a kilometer deep, twice what was previously thought.