Image Credit: Photograph by Matthias Hauser, National Geographic Your Shot.
A Jungle Down There
A hiker is dwarfed by the massive proportions of Hang Son Doong, the largest cave in the world, located in Phong Nha-Ke Bang National Park in Vietnam.
It is more than two miles long and, at some places, more than 600 feet high.
Where the ceiling has collapsed, allowing sunlight to spill in, vegetation grows heartily.