Such caves are open to experienced spelunkers or caving enthusiasts and guided visits, although some portions may be closed seasonally or permanently for conservation purposes.
There is a warning sign outside the cave opening with safety rules including one that only experienced spelunkers should enter it.
In the 1960s, the terms "spelunking" and "spelunker" began to be considered dclass among experienced enthusiasts.
It contains the remains of undetermined victims based on human bones found by spelunkers at the site.
The player controls a spelunker who explores a series of caves while collecting treasure, saving damsels, and dodging traps.
It's possible to unlock the damsel as a playable character; gameplay is identical, except that the player encounters spelunkers to rescue.
Non-solutional caves are carved out by weathering and are typically of smaller size and of little interest to spelunkers.
One study showed that caves with ceiling heights greater than 15 m above the floor were virtually protected from spelunkers.
