The Ancient Mississippian Capital Where Ceremonial Plazas and Earthworks Still Stand After 1,000 Years

Cahokia Mounds

Most folks don’t know America had a city bigger than London back in 1200 CE. Right across from modern St. Louis, Cahokia was home to 20,000 people, massive earth pyramids, and a culture that shaped the Midwest. They built it all without wheels or metal tools. Here’s the story.

The Ancient City Built Into The Landscape

Cahokia was America’s first real city. Built between 1050-1350, this huge settlement spread across the rich Mississippi River valley near today’s Collinsville, Illinois.

At its peak, 120 dirt mounds of different shapes dotted the landscape. The city covered 6 square miles of well-planned neighborhoods, open spaces, and ceremony areas.

Cahokia grew to at least 15,000 people by 1100, with some counts reaching 20,000. No other Native American city north of Mexico ever got this big.

Monks Mound That Towered Above The Mississippi Valley

The huge Monks Mound still stands out today. At 100 feet tall, it’s bigger than any other ancient earthwork in North America. Its base covers a massive 14 acres of land.

Building it took more than 14 million baskets of dirt, each one carried on someone’s back, and people started building this giant structure around 900.

French monks who lived nearby in the 1800s gave the mound its current name.

How They Built Mounds Without Modern Tools

Workers carried loads of dirt in woven baskets on their backs, one at a time.

Without horses or wheels, everything moved by human power alone. Yet the building skills were good enough to make structures that still stand nearly 1,000 years later.

Builders layered different dirt types for strength. Clay, sand, and soil created strong, water-resistant mounds that wouldn’t wash away.

The Sacred Grand Plaza Between The Mounds

The heart of Cahokia was its massive Grand Plaza. This 50-acre open space was made by leveling a natural hill using thousands of baskets of dirt.

Big mounds surrounded this huge area, with the mighty Monks Mound at the northern edge. The plaza faced the main directions, matching Cahokia’s view of the world.

Created around 1050 during Cahokia’s fast growth period, this meeting place changed the city. Thousands could gather here for rituals, games, and trading.

For hundreds of years, the Grand Plaza stayed Cahokia’s main spot.

Platform Mounds Where Chiefs Lived

Flat-topped mounds held wooden buildings where leaders lived and ruled. These structures lifted rulers above regular people, showing their special status.

Placed carefully around plazas, these mounds created sacred areas. Some formed groups that might have been neighborhoods for important families.

Building happened in stages, with mounds growing taller over time. When buildings needed replacing, people often burned them, added fresh dirt, and built new ones on top.

Ridge-Top Mounds Marking Sacred Boundaries

Long, ridge-shaped mounds marked edges of ceremony spaces across Cahokia. These earthworks created clear lines between sacred and everyday areas.

The most impressive one, an 1,800-foot path called “Rattlesnake Mound,” connected important areas. Built pointing 5 degrees east of north, it lined up with sun and star positions.

Burial Mounds Honoring The Powerful Dead

Round mounds throughout Cahokia held burials of high-ranking people. The most studied one, Mound 72, contained fancy graves that showed Cahokia’s social order.

Important burials included special items from far away. Shell beads, copper items, and well-made tools marked the dead person as important.

Some burial mounds showed signs of human sacrifice. The way bodies were placed often followed specific patterns with special meaning. Certain mounds were only for the elite.

Where you were buried and how big your mound was showed how important you were in life. Multiple people were often buried together in meaningful ways. These groupings might show family ties or spiritual connections.

Mound 72 Where Sacrifices Took Place

Mound 72 holds over 250 burials dug up in the 1960s. This medium-sized ridge mound had surprising secrets under its surface.

The main burial had a man lying on a bed of 20,000 marine shell beads. These precious beads formed the shape of a bird with spread wings.

Some bodies in the mound were missing hands and heads. Nearly two-thirds of the people appear to be sacrifices rather than natural deaths.

One mass grave had 53 young women arranged in neat rows. Another held four men with their heads and hands cut off.

Mound 72 was made around 1050 during Cahokia’s quick rise to power. Its carefully arranged burials suggest complex death rituals tied to Cahokia’s beginning.

Lost Mounds Destroyed Before Preservation

Many of Cahokia’s original mounds were destroyed before they could be protected. Farming, roads, and building wiped out irreplaceable mounds. St. Louis once had its own impressive mound group.

Now only Sugarloaf Mound remains from this once-large collection. Cahokia originally had nearly twice as many mounds as survive today. Old maps show numerous mounds now completely gone.

Early attempts to protect the site came too late for many mounds. By the time preservation efforts began seriously, dozens of mounds had already disappeared.

How The Mounds Survived Centuries Of Erosion

Cahokia’s mounds lasted nearly 1,000 years through smart building techniques. Different layers of soil types created stable inner structures.

Basket-loaded dirt was packed down firmly during building. This dense material resisted sinking and washing away. Clay tops covered many mounds, keeping water out.

This weatherproofing helped preserve the earthworks through centuries of rain and snow.

Visiting Cahokia Mounds

You’ll find Cahokia Mounds at 30 Ramey Street in Collinsville, Illinois. This UNESCO World Heritage Site preserves 2,200 acres with 80 remaining mounds.

Climb the wooden stairs to the top of Monks Mound for amazing views. On clear days, you can see the St. Louis skyline from the top.

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