Son Doong - World's largest cave

The Son Doong Cave in Vietnam is the biggest cave in the world. It has it's own underground [j](http://oxalis.com.vn/son-doong-info)ungle and river, and even it's own cloudsystem. It is so big, 40 storey skiyscrapers would fit within its walls.

The Local Ho Kanh discovered the cave entrance in 1991, but it was not until 2009 that Brittish Cavers were the first to explore the massive cave. It is only open for tourists since 2014.

Inside the darkness they so far discovered five new albinolike species.

An Expedition into the cave takes 5 days and 4 nights.