Cave Diving

Members of an Australian team of cave divers recently set a new depth record during a search to find the source of a mysterious New Zealand river. The team's mission, partly funded by National Geographic, was to discover the source of the Pearse River on New Zeland's South Island.
The Pearse River originates out of the side of a mountain and appears to get its water from a huge underground cave system, though no one has yet found the true source.
The dive team was exploring this underground cavern, which may prove to be the world's deepest cold-water cave, when they reached the record-breaking depth of 636 feet (194 meters). Despite reaching this incredible depth, the divers said the cave continued on much deeper with no end in sight.
To safely reach and return to such depths, the team constructed an elaborate system of "habitats" at different points in the cave to allow the divers to decompress, rest and warm up from the extremely cold (43-degrees F.) water temps. The team plans to return to the site next year in another attempt to reach the end of the cave and find the river's unexplained source.

To read more about this record breaking dive and see video from the cave and the diving habitats, go to Record Cave Dive Leaves Mystery