Enlarge By Dan Vergano, USA TODAY Archaeologist George Bey examines a shard of pottery found buried in the floor of a home at Kiuic. Archaeologists find new clues why the Maya left YUCATAN, Mexico — Bird calls ring from the forest, echoing amid the crumbling ruins whose darkened doorways have long beckoned explorers and scholars. The Maya ancients who built the ruins of Kiuic (kee-week) here fled those doorways in a hurry, an international archaeology team now realizes. Left behind may be frozen-in-time clues to the fabled collapse of their civilization. "Why did they leave? That's the question," says archaeologist George Bey of Millsaps College in Jackson, Miss. The ancient Maya fled Kiuic, nestled in the Puuc (pook) foothills of the Yucatan, around 880. "Things were going full-bore, construction was underway. And things stopped," Bey says. TRANSCRIPT: Prof. George Bey answered your Maya questions Archaeologists have explored Kiuic's ruins for more than a century, but working since 2000, Bey and colleagues are now reporting the first evidence of this rapid abandonment. USA TODAY was invited to the site to see what has been uncovered in the latest excavations. The "classic" Maya peopled the lowland forests of Central America during Europe's Dark Ages, building a civilization of pyramids, palaces and slash-and-burn "milpa" farms made by burning trees and planting seeds in the ash. Maya rulers oversaw city-states that warred with one another, created elaborate calendars and lasted centuries. The abandonment of those monument-strewn centers stands as one of archaeology's most-debated mysteries. The "collapse" was underway in modern-day Guatemala by 800, but didn't take place at Kiuic until almost a century later. Preserved almost like Pompeii Farther north, at centers such as Mayapan, pyramids and temples stayed in business until the arrival of Spain's conquistadors in the 1500s. The Maya people themselves remained, of course, with millions living today in Central America, from modern-day El Salvador to Mexico. Scholars are entranced with the ruins at Kiuic that still bear the last traces of their owners' flight, a Maya version of Pompeii, the entombed town of Roman archaeological fame. Overlooked and overgrown for more than a millennium, a variety of clues now beg for interpretation: • Walls, perfectly laid out with corner and vault stones, lying flat on the ground and waiting to be erected atop the second floor of a palace. • A half-finished plaza, one side stuccoed and completed, the other composed of bowling-ball-sized stones. • Pots and grinding stones left neatly in homes, awaiting their owners' return. At Kiuic, "the evidence for rapid abandonment now appears more compelling," says archaeologist Takeshi Inomata of the University of Arizona-Tucson, who heads efforts to investigate the Maya settlement of Aguateca in Guatemala, a site suddenly abandoned in 830 during warfare. "It is a very important discovery." Pumas roam the forest lining the overgrown trail leading out of Kiuic. Stones crumble underfoot on the tree-bedecked hillside, threatening to tumble visitors to the forest floor. Once a stair built of the stones, the Escalero al Cielo (Stairway to Heaven) leads to ruins of a temple courtyard and many homes that await 200 feet above. "The climb kept away looters, and also sometimes older archaeologists," says Tomás Gallareta Negrón of Mexico's National Institute of Anthropology and History, a co-director of the site with Bey and William Ringle of Davidson (N.C.) College. Gallareta Negrón has pioneered efforts to turn the site into a nature reserve and education center. Kiuic has been visited by archaeologists since at least 1841, when John Lloyd Stephens, the so-called American Traveler, recorded the site for his Incidents of Travel in Yucatan, a best seller of the pre-Civil War era. Some of the ruins he noted at that time still stood there this summer, such as the three-story-tall Yaxché pyramid and Kuche palaces. But the Stairway to Heaven homes high above the site now attract as much, or more, attention from the archaeologists. During excavations last year, archaeologists found pottery and stone tools left in place inside homes, including a wealthy farmer's kitchen room perched on the edge of the hill. Corn grinding stones called metates still rest on their sides next to doorways, at the ready for preparing another meal. In June, excavations revealed more pottery left neatly under another collapsed roof in the farmer's home. And under the floor of the main room, researchers found the site of a double burial. "We think these are ancestors of some kind," a burial arrangement in line with the practices of the ancient Maya, says archaeologist Stephanie Simms of Boston University. "They certainly merited special treatment," she says, buried with jade beads and elaborate stone tools. The owners never returned, Simms says. "People left the hill in haste, they didn't take everything with them, a lot of artifacts were found." Says anthropologist Rani Alexander of New Mexico State University-Las Cruces: "Rapid abandonments are rare finds for archaeologists. The new information at Kiuic offers another take on the Maya collapse." Drought, disease, warfare, corn-borers, worn-out soils — almost as many theories as ruins abound to explain the collapse. "The Maya were not a single people. There were numerous regional languages and numerous regional cultures," Ringle says. Whatever led to the rapid abandonment at Kiuic will offer only clues to collapses elsewhere, not some sort of final word on the large-scale emptying of centers that took place across the Maya world. The Puuc region has its own particular architecture, marked by small columns along tops of walls, the "colonette" style. But the palaces and temples conform to classic Maya styles, long row-houses facing each other across a central plaza. They built rooms whose narrow stone vaults simply leaned into each other, unlike true arches. Maya elite took the high ground Towering trees bite into the limestone blocks fronting the ruins at Kiuic, and they hide dozens of ruins there from visitors' eyes. Once the trees only hugged the ridge tops, and the land below was cleared for plazas and corn. Today the site is thick with trees, vegetation and ticks, and years of swallow droppings have left a signature stench. Kiuic's population boomed, reaching perhaps 4,000 inhabitants, just as the centers more than 200 miles farther south, at Tikal, Copan and Aguateca, suffered abandonment. "Undoubtedly there were some people who arrived here from that time, but Kiuic had already been thriving then for centuries," Bey says. The growth saw the elites move up the Stairway to Heaven (Gallareta acknowledges he is the Led Zeppelin fan behind the name) from which they could survey their fields. Around that time, 850, populations swelled throughout the Puuc foothills, perhaps most notably at the city of Uxmal. Now a World Heritage Site about 20 miles north of Kiuic (as the crow flies, not by driving), Uxmal became a capital of the Yucatan Maya for centuries afterward. The newcomers likely added to already-growing populations. But that growth just stopped in the hills at Kiuic and nearby sites, which had been occupied from 900 B.C. onwards by the Maya. "When they left, they didn't come back," Bey says. "We know where they went — there are millions of Maya living today closer to the coast. Why would they leave here and not return for the things they left?" Warfare, suggests Inomata, whose Aguateca site in Guatemala is surrounded by walls. However, Kiuic and the other towns close by show no signs of fortifications. The only warlike signs discovered are spear points dug up in the central plaza. Another possibility is a long-term drought that dried up the choltuns, large holes dug in the limestone floors of the forest to contain water. Still that wouldn't explain why people never returned after 1,900 years of occupation. Choltuns seem to have only come into widespread use in the Puuc a few centuries before the abandonment, so people had made do without them before. The careful packing of homes at the Stairway to Heaven points to a methodical retreat, not a plague or war, as well as another riddle. The whole ancient Maya way of life centered on ritual destruction of old homes and goods (smashed bits of pottery underlying the floors of structures serve as one of the handiest dating devices available to archaeologists) as a starting point for building anything new. The whole idea of a widespread catastrophic collapse of the classic Maya is overstated, Alexander says, suggesting centers likely went through many cycles of building, abandonment and reuse. So for now, the archaeologists will continue exploring these questions next summer. Residues in the pottery at the Stairway to Heaven should precisely time its abandonment, through carbon dating. Burnt wood left amid the burials should similarly time the site's construction. The team will keep asking questions with each new bit of evidence, aiming to uncover clues to Kiuic's collapse and the wider fall of a civilization. "Kiuic is just one of many sites," Bey says. "What's important is the research there. What we are learning at Kiuic is crucial for a rethinking about the rise and fall of the Maya civilization in this part of the world." Archaeologist George Bey of Millsaps College answered your questions on the Maya civilization. Digging into 'Maya Pompeii' Guidelines: You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. You share in the USA TODAY community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language decent. Use the "Report Abuse" button to make a difference. Read more