Digging and dreaming about the Cahokia Indians

Temples and homes of chieftains stnd bold on large, flat-topped mounds of earth. The sun god lives on the highest, a massive four-terrace mound. Wooden buildings with thatched roofs are clustered around plazas.

A wooden post wall circumscribes much of the community. Beyond this wall more homes, utility buildings, and fields of squash, maize, and beans stretch toward the horizon.

This is how archaeologists imagine the Cahokian Indian civilization looked some 800 years ago, based on what they have pieced together from their excavations near Collinsville, Ill.

The Cahokia Mounds Historical Site is the largest known prehistoric community in North America, north of the Rio Grand. It includes an astronomical finding called Woodhenge, a prehistoric solar calendar.

As many as 500,000 people visit the site annually. This summer a field school, sponsored by the Cahokia Mounds Museum Society, enables interested amateurs to participate in digs at $75 for two weeks.

The archaeologists who dug and dreamed at Cahokia over the past several decades, found evidence of a complex and possibly urban society. At its height -- probably a 100-year period between AD 1050 and AD 1200 -- Cahokia was inhabited by 10,000 to 30,000 people.

"We think it was a class society," says Jim Anderson, site superintendent. "There were various social classes and specialists -- people who manufactured things; and that's part of the definition of urban."

There was probably a military class as well, he adds. Nobles and clans or families formed around lesser leaders and a "sun god" presided over all.

"We've got evidence of trade," Mr. Anderson says. "Apparently the Cahokians traveled up and down the Mississippi in dugout canoes as far as the Gulf of Mexico."

They often traded for shells used in jewelry, which probably had a religious function.

What remains of this monumental civilization are the mounds and material fragments and patterns in the dirt -- shards stone tools, house foundations, game stones, arrowheads, house patterns, and copper staffs.

In 1925, the State of Illinois bought 143 acres around what is now known as Monk's Mound, named after a group of Trappist monks who lived in the area from 1809 to 1813.

Monk's Mound, terraced in four levels, is 1,037 feet long and 790 feet wide. A temple once stood on this mound, in which the "sun god" is believed to have dwelled. Mound and temple towered 15 stories above the flood plain.

Today, the 1,200-acre historical site, located on US 40 between East St. Louis and Collinsville, is operated by the Illinois Department of Conservation. It includes a small museum, which displays miniature scenes giving an overview of the prehistoric community.

Outside the museum, there is a life-size reconstruction of a thatch-roofed, mud-plastered wood house, a dugout canoe, weaving apparatus, and a garden surrounded by a wood post wall.

Visitors may hike to Monk's Mound, Twin Mounds (the most prominent other than Monk's), the Sacrifice Mound (where 300 human skeletons have been unearthed), the plaza, the palisade, the compound, and Woodhenge.

Woodhenge, an astronomical observatory comparable to Stonehenge in England, is the most enthralling find to date.

A circle of wooden posts has been reconstructed to demonstrate how the Cahokians identified the summer and winter solstices and the spring and fall equinoxes by sighting perimeter posts against the sun from an observation post in the center of the ring.

Other posts marked the rise and fall of Capella, one of the brightest stars in the night sky.

The function of Woodhenge has been sustantiated only in the last several years, although its first curious clues -- large circles of pits -- were exposed in a federally funded highway salvage program in 1961.

The Illinois Department of Conservation has drawn a master plan for the restoration of the central portion of the community -- to return houses to their foundations, temples to their mounds, and red cedar posts to Woodhenge.

A construction site for a larger museum has been selected, one which would interpret the site more thoroughly.

"In about five years, we hope to inaugurate the museum," says Mr. Anderson. "Certainly there is much we have yet to learn from the Cahokians. At present, less than 2 percent of the site has been carefully excavated."

Until the project is complete, we can only speculate what prehistoric revelations will come from these ancient students of the stars.