Caving—also occasionally known as spelunking in the United States and potholing in the United Kingdom—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.

The challenges involved in the activity depend on the cave being visited, but often include the negotiation of pitches, squeezes, and water (although actual cave diving is a separate sub-specialty undertaken only by very few cavers). Climbing or crawling is often necessary, and ropes are used extensively for safe negotiation of particularly steep or slippery passages.

Caves have been explored out of necessity (for shelter from the elements or from enemies), out of curiosity or for mystical reasons for thousands of years. However, only in the last century or two has the activity developed into a sophisticated, athletic pastime. In recent decades, caving has changed considerably due to the availability of modern protective wear and equipment. It has recently come to be known as an "extreme sport" by some (though not commonly considered as such by its practitioners, who may dislike the term for its perceived connotation of disregard for safety).

Many of the skills involved in caving can also be put to use in mine exploration and urban exploration.