Watch: Climbers conquer massive cave
20 March 2014 Last updated at 14:56 GMT
Two men have successfully climbed out of the one of the world's largest cave chambers - using only a safety rope.
Climbers Stefan Glowacz and Chris Sharma spent two weeks climbing more than 300 metres out of the Majlis al Jinn cave.
They first abseiled to the bottom before starting their climb, in Oman in the Middle East.
In order to sleep during their climb they had to build suspended platforms. The challenge had never been attempted before. Check out the video,