As thick tangles of vine fall beneath his blade, he pushes into a clearing, then suddenly staggers back.
The fanged mouth of a primordial stone beast gapes toward him.
Before him rise the crumbled ruins of an enormous portal of rock, black with age but with a colossal grandeur not yet lost -- a fine example of what archaeologists call a "zoomorphic portal" or, more popularly, a "monster mouth gate."
What was once the gateway to an ancient Mayan city, built circa 700 AD and mysteriously abandoned four centuries later, stands before him.
He has found the lost city of Lagunita.
Discovering lost worlds
Now that the planet has been mapped, circumnavigated, measured and tagged in every way imaginable, the age of explorers discovering new worlds seems a quaint memory.
But there are still adventurers exploring forgotten corners of the globe, and some find astonishing things.
One such explorer, part Indiana Jones, part Magellan, is Slovenian archaeologist Ivan Šprajc.
The sprightly Šprajc wears the weathered face of a man who has spent much of his 60 years beneath a hot sun at excavations, or hacking his way through dense jungle.
He has been the first to see ancient pyramids, 30 meters high, that he spotted in aerial photographs from his office among the Baroque Mitteleuropean cobbled streets of Ljubljana, Slovenia, some 10,000 kilometers away.
But in terms of the thrill of discovery, it doesn't get any better than his encounter with Lagunita's monster portal.
Fortune and glory
What does it feel like to find a lost city? "It's a victory," says Šprajc, "especially when the efforts are long. On several occasions we've had two, three weeks of just cutting through the bush to get to some location, without knowing what we would find. When we get to the site it feels like a big victory, like we've done it. If it had been easy, then other people would have done it already."
Since 1996, he and his team have discovered more than 80 ancient Mayan cities in the jungles of Mexico, few of