Ivan Trifonov is a world-renowned Austrian daredevil. He currently holds four Guinness World Records, including the one you are about to see. As a tribute to Jules Verne, author of "Journey To The Center Of the Earth", Ivan completed this feat. He decided that he wanted to be the first person to fly a hot air balloon underground. It sounds impossible...but... Trifonov and his crew begin blowing up the balloon. youtube The target is Mamet Cave, the mysterious abyss of Velebit Mountain, Croatia. youtube Up goes Ivan. youtube var OX_ads = OX_ads || []; OX_ads.push({ 'auid':537104098, 'slot_id': 'slot537104098_543803adb15fa' }); Welp,...