It seems crazy, but if you can't think of what the hell you are doing there, you can do it. In the jungle of San Luis de Potosí, in Mexico, one can grab with ropes and jump into a cave in a vertical fall of 400 meters.
This is the cave called the Basement of the Swallows and was discovered by some Americans in 1966.
A dream for every adrenaline lover in its purest form. There are only 12 seconds in the fall but surely they do not leave indifferent even the craziest of hearts!
Via, Rob You Tube