Cave of Swallows. Natural miracle: Swallow Cave Here is a short video about jumping into the swallow cave
I’m sure many have watched James Cameron’s film “Sanctum” (which, by the way, means “Purgatory”), but few know that the cave that became the final refuge for most of the heroes really exists. And its name is “Cave of Swallows” or “Sótano de las Golondrinas”. The cave is located in Mexico, in the state of San Luis Potosí.
Nature is brilliant in its creations, sometimes it delights and fascinates. Thus, the Cave of Swallows, which is located in the tropics of central Mexico, attracts base jumpers and cavers from all over the world. Its size is impressive, its beauty delights, its originality fascinates. The Cave of Swallows ranks 2nd in depth in Mexico, and 11th in the world. It descends to the depths of the Earth to a depth of 376 meters, which is comparable to the height of the Empire State Building (381 m without the spire).
Hiding in the thickets of tropical vegetation, the entrance to the cave looks like a huge hole in the mountain with a diameter of about 55 meters. The hole is almost round and beckons into its depths with twilight.
Only a narrow footpath and a dirt road for jeeps lead to the Swallow Cave. Ecologists strive to preserve the unique ecosystem; to achieve this, they introduce a number of restrictions for researchers.
Very often the Cave of Swallows seems smaller than it actually is. Having the shape of a kind of bottle: first a 55-meter vertical “neck”, then expanding to 130-160 meters, it is a serious test even for very experienced and physically trained base jumpers and speleologists.
In order to preserve the unique ecosystem for which the Swallow Cave is known, only one path is allowed for descents with an area for attaching equipment and ropeways.
The cave became home to a colony of swallows, which consists of several million individuals. That's why it got its name. In order not to disturb the quiet life of birds, descents are allowed only at certain times: from 12 to 16 hours. In addition, colliding with a flock of birds during a free flight is very dangerous.
The Swallow Cave has many gentle slopes and stepped passages. So going down, let alone climbing, the slopes is a difficult task. Even for professionals, the climb can take about an hour and a half.
The bottom of the cave is strewn with fragments and chipped walls and bird droppings. Together with rainwater, this became food and shelter for many species of insects and reptiles. The air is filled with the smell of rot, fungi, mold and bacteria. And although it is safe to be at the bottom of the Swallow Cave, a long stay should be carried out with additional equipment and filters.
A free fall without a parachute to the bottom of the cave will take approximately 12 seconds. Daredevils who decide to jump from a slope must plan everything clearly, because the parachute can be opened only at a strictly defined time: at 6-7 seconds of the fall.
The Swallow Cave has recently become a real Mecca for base jumpers and speleologists. This allowed local residents to earn income from tourism (before this, only agriculture was developed). However, another problem arose - environmental pollution.
Photos from open sources
The famous Mexican Cave of Swallows is increasingly attracting paranormal researchers, since here there is the most intense accumulation of so-called “flying rods” - a kind of UFOs, the study of which is of great interest for ufologists and at the same time enormous complexity due to “non-materiality” and too fast moving these strange objects. (website)
Scientists first started talking about “flying rods” more than ten years ago. But it was the Swallow Cave that became the place where this paranormal phenomenon was noted in large numbers.
Photos from open sources
Extreme sportsman Mark Lytle and his friend once went to the Swallow Cave to skydive. This Mexican failure is actually unique for such an extreme sport, since it is more than half a kilometer deep, and the cave itself widens towards the bottom and has a side exit to the outside.
Mark and his friend not only jumped, but also filmed their flights over the abyss. What a surprise they were when the videos captured showed not only themselves and numerous swallows (hence the name of the cave), but also some mysterious bright rods. Moreover, a considerable accumulation of them was noted in this place.
“Flying rods” are incomprehensible energy formations with no material shell. From this, scientists concluded that the rods may be representatives of a parallel world. It is no coincidence that one of the leading researchers of this phenomenon, Jose Escamyo, when he saw the footage taken by Mark Lytle, was literally delighted. The fact is that “flying rods” are recorded all over our planet, but it is rarely possible to catch them on camera, and therefore information about them is very scarce.
Photos from open sources
These energy clots move through space at enormous speeds - from two kilometers per second and above. They can only be recorded using video recording, but how and where should it be done? And suddenly such luck - a cluster of “flying rods” was discovered in the Cave of Swallows!
Photos from open sources
Scientists do not yet know exactly what these clots of energy are, but today they are making the assumption that the Mexican failure may be a portal through which these UFOs penetrate into our reality. It is not given to us to know and understand yet what it is, or for what purpose these UFOs appear in our world. Most likely, they are simply studying us, since they are recorded in all corners of the Earth. However, some scientists admit that this may be an invasion of extraterrestrial intelligence with the aim of enslaving our civilization. True, as leading ufologists say, this is the most primitive theory, based on underdeveloped human consciousness, suffering from aggression and misunderstanding of the true laws of the Universe...
Cave of Swallows(Spanish Sótano de las Golondrinas, English Cave of Swallows) - of karst origin in Mexico, in the state of San Luis Potosi. The shape is a cone-shaped (or bottle-shaped) karst sinkhole expanding downward.
The hole in the Swallow Cave on the surface of the earth has an elliptical shape (round in plan, as it is located on a slope) and has dimensions of 49 by 62 meters, the depth of the hole is from 333 to 376 meters (the hole on the surface is located on a slope).
At the bottom it has an elongated shape, close to an oval with one almost flat side. The volume of space is estimated at 33110 m³. The bottom and passages to deeper levels, which probably exist, have so far been poorly explored.
A narrow footpath and a dirt road lead to the Swallow Cave, which can only be driven by off-road vehicles.
Its dimensions are such that it can easily accommodate the famous New York skyscraper Chrysler Building.
The Cave of Swallows was known to people who inhabited this area since ancient times. The first documentary research was carried out on December 27, 1966.
In recent years it has become a favorite place for base jumpers.
Part of the filming of the film “Sanctum” took place there.
The Spanish name of the cave comes from the Mexican name for swallows - Golondrinas. However, it is inhabited by swifts of the Black Swift species and parrots of the Mexican Aratinga species.
Flora and fauna of the Swallow Cave
In the morning, flocks of birds fly in a spiral, gaining altitude until they reach the exit. In the evenings, the swifts return, and they dive in flocks of several dozen individuals until they reach the level of their nesting area there. Observing the behavior of birds has become one of the favorite activities of tourists visiting its entrance.
The Swallow Cave is also quite densely populated by insects and snakes. Due to the large amount of guano on the floor of the cave, evaporation, the presence of a large number of bacteria in the air, and fungi and mold on the walls.
The floor of the pit is covered with the excrement of millions of birds. This excrement, rainwater, and debris from the surface are the food base of the numerous animals on the cave floor. There are centipedes and insects, snakes and scorpions. The air is filled with odors, fungi and bacteria. It's possible to be at the bottom without a breathing mask, but cavers who want to explore the far reaches should bring additional equipment.
To protect nature, Swallow Cave and its unique ecosystem, the researchers agreed to use only one launch point. This place is equipped with rope bolts. Another point is the time of day, birds fly out of it in the morning and arrive in the evening. Explorers and especially BASE jumpers should not disturb the peace at this time of day.
In terms of depth, it is the 2nd deepest place in Mexico, and the 11th deepest in the world. It is the depth that attracts many tourists and especially fans of such extreme sports as base jumping (parachute jumping from any heights).
A person without a parachute would fall for approximately 12 seconds, from top to bottom. As a result, many extreme sports enthusiasts take up the challenge to jump off the edge.
There was also a recorded case when a medium-sized balloon was carried from the bottom of the cave through its 45-meter entrance.
Swallow Cave is also a popular destination for experienced cavers. The descent to the bottom can take about 20 minutes. They go down there using a rope. But the way back is a real challenge to your strength!
The explorer must climb up a single rope using clamps, which is very tedious. This is a minimum of 40 minutes of enormous stress, and even for extremely trained researchers this is a serious test. And for normal, physically fit people, the journey takes about two hours.
There is also a psychological point here: the height is not the only problem, the width makes it much lighter and it looks smaller than it really is. Our brain cannot accurately estimate real distances. Therefore, the climber forces himself to work hard without any visible progress.
The Swallow Cave has many gentle slopes and stepped passages. So going down, much less climbing, is a difficult task.
The Cave of Swallows became famous thanks to the James Cameron film called Sanctum. It is located in the Mexican state of San Louis Potosi. The cave expands downwards in the form of a cone; at the very entrance its width is 49 by 62 meters, gradually expanding to 303 by 135 meters. The depth of the cave ranges from 333 to 376 meters. In terms of volume, it is one of the largest caves in the world, as well as one of the deepest in the world. It can completely fit the New York Chrysler Building
Local residents have known about this cave for a very long time, dating back to ancient times, and the first recorded exploration took place on December 27, 1966 by researchers Evans, Borland and Stearns 
The name Swallow Cave comes from the huge number of birds living in it. Among them were not only swallows, but also many other species, including parrots. Every morning, flocks of birds fly out of the cave, rushing into the sky, and in the evening they fly back, descending in large groups directly inside. This is a very impressive spectacle when birds rush in free fall straight into the abyss, stopping only when they reach their nests. Numerous tourists love to watch this process. 
The temperature in the cave itself is quite low, and there is vegetation only in the upper part, where after the rains streams and waterfalls appear, cascading into the cave. Its bottom is covered with a thick layer of broken rocks and bird guano, and is home to many insects, scorpions and snakes. There is also a narrow drainage well that goes further to a depth of 512 meters 
The Swallow Cave is popular among mountaineering enthusiasts. Since the entrance is not covered with a thick layer of foliage, the descent usually begins lower, where special stakes for climbers are driven in. The descent to the bottom of the cave takes about 20 minutes and is quite dangerous. The ascent will take up to 2 hours for a trained climber. If a person jumps into a cave without a parachute, his free fall time will be about 10 seconds. This place is very popular among sports enthusiasts who practice base jumping. Once upon a time, a hot air balloon with a diameter of 49 meters was planted at the bottom of the cave. 
The video shows an example of base jumping.