Photojournalist Martin Edström hopes to bring the cave to as many people as possible. He also wanted to document Son Doong in its relatively untouched state, just in case those construction plans go through. So he set out with a team in January 2015 to build a virtual tour of this roughly 2.5-mile-long (four kilometers) cave.
Digital "tourists" can see 360° panoramic views of key sections of Son Doong on a smartphone, tablet, or desktop computer. Some of the largest passageways are about 300 feet (91.4 meters) wide and over 600 feet (182.9 meters) high.
Some pictures of Son Doong from NatGeo:
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