Septuagenarian adventurer flies hot-air balloon into cave 200 meters deep

A seventy-year-old Austrian adventurer successfully landed a hot air balloon in a cave 200 meters deep in the Velebit mountains in southern Croatia earlier this month.

Ivan Trifonov, an experienced balloon pilot and holder of four Guinness records, decided to fly down, touch the cave's bottom and fly out of the cave, in a never-before attempt at flying a hot-air balloon underground.

Trifonov's flight on September 18 came exactly ten years after fellow Austrian adventurer Felix Baumgartner had pulled off a parachute base jump on the same spot.

The inspiration of Trifonov's adventure was "Journey to the Center of the Earth," a book by the famous author Jules Verne, and he chose Mamet Cave as his entrance to the underground world after he saw a video of Baumgartner's base-jump.

For flying underground Trifonov had to use a specially designed hot-air balloon—one smaller than usual, and the pilot had to sit on two gas tanks linked with steel pipes instead of the usual basket.

The Mamet Cave is a 206-meter-deep abyss in the karst landscape of southern Velebit mountains, near the town of Obrovac in the hinterland of Dalmatia.

The cave, shaped in the form of an upended funnel, is famous for its impressive pit entrance which is some 60 meters wide.

This historical hot-air balloon flight took about 25 minutes, from the initial take-off on surface, through touching the bottom of the cave, and flying out and landing back on surface.

Trifonov said he doubted anyone would ever repeat his descent.

"This was a very difficult thing to do. A very difficult project. One must have the right balloon, the right weather and the right support. It was very hard, and I don't think anyone else will ever repeat this feat. I sincerely doubt it," Trifonov said after the flight. — Reuters