Srilanka, Oct. 19 -- Caving, also known as spelunking (US) or potholing (UK), refers to exploring natural underground passages or caves as a recreational activity. Due to how potentially dangerous it can be, caving as an activity is sometimes considered to be an extreme sport. Cavers find this label to be a bit of a misnomer, as caving is far safer than most sports labelled as such.

Caving, and its underwater equivalent, cave diving, has a bad reputation, as there are infamous incidents of caving going horribly wrong that trigger most people's claustrophobia. But caving can be an incredible experience, with each excursion offering a rare glimpse into nature's hidden landscapes.

Caves, and by extension, the world beneath our feet, has be...