Cahokia Mounds reveal the breathtaking brilliance of ancient Mississippians in Illinois

Cahokia’s Rise as America’s First Ancient Metropolis

Long before Europeans set foot in America, a true city rose from the plains near modern-day St. Louis.

Around 1050 CE, thousands of Mississippian people built Cahokia, a sprawling urban center that soon housed 20,000 folks—more than London at that time.

They hauled 22 million cubic feet of soil in baskets to build Monks Mound, a massive 100-foot platform for their ruler’s home.

Nearby stood Woodhenge, a circle of tall timber posts that tracked the sun’s path across the sky with stunning skill. The city boasted plazas, homes, and over 120 mounds, all laid out with clear purpose.

This first American metropolis thrived for 300 years, then slowly faded away.

The story of this ancient urban wonder comes to life at Cahokia Mounds State Historic Site in Illinois.

Farmers First Settled in the American Bottom Around 800 CE

Small farming villages popped up along the Mississippi River around 800 CE. The Mississippian people found the rich floodplain perfect for growing corn, beans, and squash.

They built simple homes and farmed together in small groups.

The good soil made growing food easy, while nearby forests and rivers gave them plenty of materials and food. These early farmers started what would later become North America’s biggest ancient city north of Mexico.

Thousands of People Suddenly Moved to Cahokia Around 1050 CE

A huge population boom changed everything around 1050 CE.

People came from all over the region, with numbers jumping from a few hundred to thousands in just one generation. Workers quickly built new homes as newcomers flooded in.

The settlement grew into a busy hub covering nearly six square miles. The fast growth meant leaders needed better ways to manage all the people and resources.

Workers Moved 22 Million Cubic Feet of Dirt to Build Monks Mound

Monks Mound stands as the biggest dirt structure in the Americas. Workers started building it around 1000 CE, carrying soil in woven baskets from nearby pits.

They used different soil types in layers – clay, sand, and silt – to stop erosion. They added special sod blocks to keep the massive structure stable.

The finished mound reached 100 feet tall with a 14-acre base – bigger than the Great Pyramid of Giza at ground level.

The Grand Plaza Could Hold Thousands for Community Events

Cahokians cleared a massive 50-acre area by hand to create their central plaza. Workers took out trees and filled in low spots to make the surface flat for big gatherings.

The plaza hosted markets, ceremonies, and games that brought people together. Important buildings and mounds lined this open space, with Monks Mound at the north end.

The carefully planned public area served as the heart of city life.

Wooden Circles Tracked the Sun and Seasons with Amazing Accuracy

Cahokians built several “Woodhenges” – large circles of tall red cedar posts that worked as sun calendars. The posts lined up perfectly with sunrise positions throughout the year.

From the center of the circle, people watched the spring equinox sun seem to rise right from the top of Monks Mound. These sun-trackers helped leaders know when to plant crops and schedule ceremonies.

Diggers found remains of at least five different wooden circles built over time.

The City Had Neighborhoods Just Like Modern Towns

Cahokia was split into different districts with specific purposes. Rich families lived near the central mounds while regular folks settled in outer areas.

Some neighborhoods focused on making pottery, others on stone tools or shell beads. The city had more than 120 mounds of various sizes and shapes.

Some held important buildings, others served as platforms for homes of high-ranking residents, and some contained burials of important people.

A Massive Wooden Wall Protected the City Center

Around 1150 CE, Cahokians built a huge wooden wall around their central area. The wall needed more than 20,000 logs from nearby forests, each placed upright in a deep trench.

Workers rebuilt this wall at least four times during Cahokia’s history.

The barrier stretched for nearly two miles, surrounding the most important ceremonial and government areas. This big project showed both building skill and the ability to organize large work teams.

Cahokia Grew Bigger Than London in the 1100s

At its peak between 1100-1200 CE, Cahokia housed between 15,000-20,000 people, making it larger than London at that time. The city became the center of a huge trade network throughout the Mississippi Valley and beyond.

People found Cahokia-made items hundreds of miles away.

Cahokia’s pottery styles, tools, and religious items shaped communities across the Midwest and Southeast.

People Played a Popular Game Called Chunkey in the Plazas

Daily life in Cahokia included plenty of fun activities beyond just work.

Chunkey was the favorite game, where players rolled stone discs and threw spears to land where they thought the disc would stop.

Big feasts brought people together, with special pottery used just for these community meals.

Farmers grew corn, squash, and other crops in the fertile fields around the city, while hunters caught deer, birds, and fish from nearby woods and rivers.

Climate Problems Started Causing Trouble Around 1200 CE

Environmental challenges began hitting Cahokia around 1200 CE. The weather changed, bringing more floods and droughts that made farming harder.

Years of cutting down trees for buildings, firewood, and the wall left the land bare and easy to erode. The soil got worn out from too much farming without enough rest.

These problems made feeding the large population harder, creating stress for the community and its leaders.

The Once-Great City Emptied Out by 1350 CE

Cahokia’s population started shrinking after 1200 CE. New construction projects became smaller and less ambitious as resources and workers became scarce.

Political problems likely grew as leaders struggled to maintain control during harder times. By 1350 CE, most people had left, moving to smaller settlements throughout the region.

What was once the greatest city north of Mexico stood largely abandoned.

The knowledge of how to build and maintain such a large urban center faded away, not to be matched again in North America until European colonization centuries later.

Visiting Cahokia Mounds State Historic Site, Illinois

Cahokia Mounds State Historic Site is at 30 Ramey Street in Collinsville, just 8 miles northeast of St. Louis.

You can explore the grounds and trails for free from dawn to dusk. Climb 147 steps up Monks Mound to see St. Louis from the 100-foot summit. Download the Cahokia AR Tour app for virtual experiences of the Grand Plaza.

Join special sunrise ceremonies at Woodhenge during solstices and equinoxes. Portable restrooms are only at Monks Mound parking lot.

This article was created with AI assistance and human editing.

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