Potholing = from Wikipedia
Caving — also traditionally known as spelunking in the United States and Canada and potholing in the United Kingdom and Ireland — is the recreational pastime of exploring wild (generally non-commercial) cave systems. In contrast, speleology is the scientific study of caves and the cave environment.[1]
The challenges involved in caving vary according to the cave being visited, but — in addition to the total absence of light beyond the entrance — often include the negotiation of pitches, squeezes,[2] and water hazards.[3] Cave diving is a distinct, and much more hazardous, sub-specialty undertaken by a small minority of technically-proficient (and daring) cavers.[4] In an area of overlap between recreational pursuit and scientific study, the most devoted and serious-minded cavers become accomplished at the surveying and mapping of caves and the formal (though usually private) publication of their efforts.
Caving became widely popular in the 1940s and '50s when a substantial caving community developed in the United States. In recent decades, the pursuit has changed considerably due to the availability of modern protective wear and other equipment. Sometimes categorized as an "extreme sport", it is not commonly considered as such by long-time enthusiasts, who may dislike the term for its connotation of disregard for safety.[2][5]
Many caving skills overlap with those involved in mine and urban exploration.