A caver in a tight squeeze in the Yorkshire Dales, England, United Kingdom, Europe

man cave caver caving pot hole holing holer spelunking spelunker underground under world erosion eroded passage passageway tube cavern formation roof constricted space air day indoors people portraits one person one man only men head and shoulders waist up crawling squeezing caves interiors potholer potholers potholing pot holers pot holing danger adrenalin adventure yorkshire dales england yorkshire great britain united kingdom europe horizontal