Perhaps the greatest Maya mystery of all is the cause of the civilization’s abrupt decline. The last dated stela erected at Tikal was put up in a.d. 869; the last anywhere in the Maya world, in 909. The causes of what University of Pennsylvania archaeologist Robert Sharer calls “one of the most profound cultural failures in human history” have been debated for a century. The stelae are no help—the collapse seems to have ended most of the carving. Most likely, researchers speculate, a severe drought devastated a society that was already suffering from overpopulation and famine.
Tikal still keeps some secrets. Scanning a map of the ruins laid out on his desk, Stuart points to an area of nameless, unexcavated mounds just south of the Lost World. “I’ve always been curious about this group,” Stuart says. “You can spend five or six years digging a site and not greatly change our understanding of Classic Maya civilization. What changes it is the fortuitous discovery of a new inscription.” His finger rests on the area. “Who knows what you might find there?”