Hidden for centuries, the ancient Maya city of Holtun, or Head of Stone, is finally coming into focus.

Three-dimensional mapping has "erased" centuries of jungle growth, revealing the rough contours of nearly a hundred buildings, according to research presented earlier this month.

Though it's long been known to locals that something—something big—is buried in this patch of Guatemalan rain forest, it's only now that archaeologists are able to begin teasing out what exactly Head of Stone was.

Using GPS and electronic distance-measurement technology last year, the researchers plotted the locations and elevations of a seven-story-tall pyramid, an astronomical observatory, a ritual ball court, several stone residences, and other structures.

(See National Geographic pictures of excavated Maya cities.)

The Maya Denver?

Some of the stone houses, said study leader Brigitte Kovacevich, may have doubled as burial chambers for the city's early kings.

"Oftentimes archaeologists are looking at the biggest pyramids or temples to find the tombs of early kings, but during this Late-Middle Preclassic period"—roughly 600 B.C. to 300 B.C.—"the king is not the center of the universe yet, so he's probably still being buried in the household," said Kovacevich, an archaeologist at Southern Methodist University in Dallas.

"That may be why so many Preclassic kings have been missed" by archaeologists, who expected to find the rulers' burials at grand temples, she added.

The findings at Head of Stone—named for giant masks found at the site—could shed light on how "secondary" Maya centers were organized and what daily life was like for Maya living outside of the larger metropolitan areas such as Tikal, about 22 miles (35 kilometers) to the north, according to Kathryn Reese-Taylor, a Preclassic Maya specialist at Canada's University of Calgary.

Head of Stone, which has never been excavated, "was not a New York or Los Angeles, but it was definitely a Denver or Atlanta," said Reese-Taylor, who called the new mapping study "incredibly significant."

(Get the full story of the rise and fall of the Maya in National Geographic magazine.)

Buried Pyramid

From about 600 B.C. to A.D. 900, Head of Stone—which is about three-quarters of a mile (1 kilometer) long and a third of a mile (0.5 kilometer) wide—was a bustling midsize Maya center, home to about 2,000 permanent residents.

But today its structures are buried under several feet of earth and plant material and are nearly invisible to the untrained eyed.

Even Head of Stone's three-pointed pyramid—once one of the city's most impressive buildings—"just looks like a mountain enveloped in forest," said study leader Kovacevich, who presented the findings at a meeting of the Society for American Archaeology in Sacramento, California.

Jungle Thick as Thieves

Head of Stone is so well hidden, in fact, that archaeologists didn't learn of it until the early 1990s, and only because they were following the trails of looters who had discovered the site first—perhaps after farmers had attempted to clear the area, according to Kovacevich.

For thieves, the main attractions were massive stucco masks measuring up to ten feet (three meters) tall. Uncovered as looters dug tunnels into the buried city, the heads once adorned some of Head of Stone's most important buildings.

The temple, Kovacevich said, "would have had these really fabulously, elaborately painted stucco masks flanking the two sides of the stairway that represented human figures, snarling jaguars," and other forms.

During the Preclassic period, Head of Stone's important public buildings would have been painted primarily in blood reds, bright whites, and mustard yellows, the University of Calgary's Reese-Taylor said. Murals of geometric patterns or scenes from myth or daily life would have covered some of the buildings, she added.

King of Stars

During special events at Head of Stone, such as the crowning of a king or the naming of a royal heir, "there would have been a lot of people—not only the 2,000 people living at the site itself but all the people from surrounding areas as well. So, several thousand people," Reese-Taylor said.

Thick gray smoke and the smell of burning incense would have filled the air. Gazing up at the temple top through this haze, a visitor might have seen "ritual practitioners" performing dances and sacred rituals while adorned with elaborate feathered costumes and jade jewelry.

During the solstices or equinoxes, the crowds would have moved farther south and higher up in the city, surrounding the buildings that made up the astronomical observatory.

"During the solstices, you would've been able to see the sun rising in line with the eastern structure, and the common people would have thought that the king was commanding the heavens," study leader Kovacevich said.

The researchers, though, are directing their gaze downward. This summer they hope to begin excavating residential structures and the observatory, as well as to possibly remove the undergrowth from the main temple.

And, by using ground-penetrating radar, they hope to bring Head of Stone into even sharper relief.