This is called the ‘Cave of Swallows‘ and if you ever were to pay a visit to this deep dark pit cave in San Luis Potosí, Mexico, then you would be tempted to call it “Swallow’s Shallows”.

This beautiful, yet touch spooky, wonder of nature is perfect for you to take a trip to keeping in spirit with this Halloween weekend. The 1094 foot free-fall makes this the largest cave shaft in the world, goes much beyond its physical attributes. The interaction of nature with its surroundings is at its splendid best in the heart of these caves.

The entrance to the Sótano de las Golondrinas, as the Cave of Swallows is known locally, is a slope section that measures 160 by 205 feet and then leads to a large room that opens up into a vertical fall straight to the bottom of the cave. The cave is inhabited by white-collared swifts, which form the most important part of the cave’s ecosystem and draw tourists to the site with their brilliant acrobats.

The birds that spend the nights in the refuge of the cave’s depths, fly to the top each morning using a technique that is similar to the movement of chopper blades, flying in circles and slowly ascending to broad daylight. While the show is all about symmetry and ‘lift’ in the morning, the evening turns out to be a spectacular synchronization of teamwork and free-fall aerodynamics.

The birds circle the entrance of the cave and at periodic intervals - a minute or two, before a batch of about fifty breaks away and enters the cave. Then they each fly to the entrance of the shaft and use free-fall to reach the bottom of the cave, before spreading their wings to break the fall!

Apart from the great spectacle, the cave is also a great spot for adventure sport enthusiasts as the vertical fall offers a great place for base jumping and one can even use a hot-air balloon to navigate. Then there is also the option of descending into the cave in the usual methods for the more sober.

Beyond everything else, the humid and dark cave will make sure it drives the spirit of Halloween home. If not for Halloween, make sure you visit the Cave of Swallows for the unique aerial show on offer- all the words in the world could not describe it!

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