Explore the ancient caves of Hang Son Doong, Vietnam. Hang Son Doong is one of the largest caves in the world and features a fast-flowing underground river. For spelunkers, exploring Hang Son Doong is the equivalent of scaling Mount Everest.
Fanad Lighthouse Cave by Stephen Emerson on Fanad Lighthouse captured on a dark, cold and windy October morning. Just below the Lighthouse to the left is a large cave that bellows with the sound of the Atlantic waves that surge in and out.