What we're driving on is mostly clay with copious amounts of limestone. The mixture turns to a slimy, clingy potter's mix at the first exposure to rain and is hard as rock when dry. It eats paint and metal in either form.

Four-wheel-drives equipped with mud tires are a must for safer travel, as are winches, spare tires, and tow straps. Fortunately, Dr. Francisco Estrada-Belli's and Jeremy Bauer's Tacomas are well-equipped with Warn 9500 winches, Hi-Lift jacks, Super Swamper Bogger tires, and Old Man Emu suspensions. Dr. Estrada-Belli's pickup is also running an ARB Air Locker in the rear differential.

The doctor is an assistant professor of archaeology at Vanderbilt and leader of the Holmul Archaeological Project, which rediscovered the Mayan city of Holmul in 2000 after its first discovery back in 1911.

Modern satellite imagery helped Dr. Estrada-Belli pinpoint the city, which ended up being three kilometers from the original map's charted location.

Now, after three years of mapping from the ground, the professor and a few of his elite graduate students are finally doing some digging in the ruins that extend out from Holmul Central, around six kilometers in every direction. All work in Guatemala is done with the permission of Instituto de Antropologia e Historia.