Caving and spelunking are two sports which are decidedly not for the faint of heart.
Quite what draws people to squeezing through the tightest of spaces is frankly beyond me, but it seems that many people still enjoy the pastime despite the enormous dangers.
Some caves are more dangerous than others, and there's one cave which led one ill-fated caver to a truly awful death.
The Nutty Putty Caves had been a popular spot for cavers, but have now been sealed off with concrete.
This was following the death of caver, John Edward Jones, in 2009. Despite being an experienced spelunker, he became stuck upside down at a particularly dangerous part of the cave known as the 'birth canal'. After being stuck for 24 hours, he eventually stopped breathing and became unresponsive after each breath drew him deeper into the wedge.
The perilous cave is located south of Salt Lake City in Utah. It got its unusual name from the soft, putty-like texture of the calyx inside it.
Nutty Putty Cave had been a popular spot with cavers prior to its closure in 2009. In fact, it had gotten so popular that it had to be closed temporarily to ensure that proper safety precautions were put in place for anyone seeking to risk taking a trip down into it.
It was reopened following this closure in May 2009, only to once again close in November of the same year.
Astonishingly, many cavers were angry at the decision to close the cave following the horrific death of Jones.
Previously the cave had been closed with a gate, but determined cavers had broken through the gate because they just couldn't stay away.
When the cave was fully sealed after Jones died, it was done using concrete and explosives. It was agreed that the cave be sealed partly due to safety concerns and also because extracting Jones' body would be too dangerous.
Local cavers were unimpressed at the decision, with many complaining that they hadn't been consulted.
Caver, Daniel Kimber, told Utah news website KSL at the time: "Just because of the tragedy, it doesn't mean you have to close it down".
Fellow caver, Kyle Parker, said: "When I found out they were closing it without us being able to say anything, to have any word on it, I thought it was ridiculous."
He added: "I think we should have a say. We understand the risks on what we're doing, and it's something we really loved to do."
Despite their protestations, Nutty Putty Cave was sealed becoming a tomb and memorial to the unfortunate Jones.Featured Image Credit: YouTube / Fascinating Horror