David McMahon Irish , 36, is a head tour guide for Venture North Safaris in Australia's Northern Territory and has to face driving through a river filled with 600 crocodiles to get to work every day. One of David's tours goes across the East Alligator River at Cahill's Crossing which is not for the faint-hearted and has claimed two lives in the past. In a video crossing the mighty East Alligator River, he is seen surrounded by the beasts. He says: "They're lined up as the diamond scale mullet and barramundi are swimming up the crossing. This is truly such a wild place."