March 8, 2013

Underwater Cave, Tonga

Photograph by Jason Edwards, National Geographic

A diver exits Mariners Cave, an underwater cavern accessible only by tunnel, on Nuapapu in Tonga. The South Pacific country comprises 170 islands, only 36 of which are inhabited.

Photos of the Island Nation of Tonga >>

Travel 365. Explore the world, one incredible image at a time.

Take a Nat Geo Trip

Select a destination or trip type to find a trip:

See All Trips »

Join Nat Geo Travel's Communities

2015 Traveler Photo Contest

  • Picture of a tree under night stars in Deadvlei, Namibia

    See the Winners

    Explore the top photos, share your favorites, and browse all entries.