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Cahokia -

Around 1000 CE, a complex metropolis thrived near present-day St. Louis, near the Mississippi, Missouri, and Illinois rivers.

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Cahokia -

Known as Cahokia, it was the largest city north of present-day Mexico. It had an estimated population of between 10,000 and 20,000 people.

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Cahokia -

The city was dominated by at least 100 raised structures, which were topped with houses, burial mounds, and other buildings.

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Cahokia -

The largest building was a terraced structure that rose 98 feet (29 m) into the air. Its base was even larger than the footprint of Egypt’s Great Pyramid of Khufu.

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Cahokia -

Little is known about this ancient civilization. But based on historians' research, it was a cosmopolitan center of crafts, trade, and architecture.

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Cahokia -

Judging by protective wooden palisades found around the city center, something started to threaten the Cahokians. By 1350, they had completely disappeared.

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Teotihuacan -

Located just 30 miles (48 km) northeast of present-day Mexico City, Teotihuacan was possibly the largest city in the Americas.

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Teotihuacan -

Once an epicenter of architecture and art, Teotihuacan was at its peak around 400 BCE. It had a flourishing artistic community, who influenced cultures throughout Mesoamerica.

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Teotihuacan -

It's estimated that more than 100,000 Teotihuacanos lived in the impressive city, filled with avenues, temples, palaces, and thousands of apartment buildings.

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Teotihuacan -

Some impressive structures include the Pyramid of the Sun, which is believed to have venerated a deity within Teotihuacan society.

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Teotihuacan -

Then there was also the Pyramid of the Moon, which was used for ritual sacrifices of animals and humans. Archaeologists have found proof beneath it, including the remains of wolves, eagles, pumas, and 12 human bodies.

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Teotihuacan -

Around 750 CE, the city burned down, possibly at the hands of invaders. It was never recovered. Archaeologists are still working to find out who the Teotihuacanos were, where they came from, and what language they spoke.

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Chaco Canyon -

From 800 to 1200 CE, indigenous people lived in more than 150 settlements around Chaco Canyon, located in modern-day New Mexico.

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Chaco Canyon -

They lived in impressive stone mansions, with hundreds of rooms. The largest house was Pueblo Bonito, at the center of the Chacoan world.

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Chaco Canyon -

The Chacoan people were farmers and traders. To water their corn, squash, and beans, they harnessed the intermittent flow of local streams through canals and ditches.

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Chaco Canyon -

They were also in contact with the Mesoamerican peoples to the south. Traders brought in goods such as scarlet macaws and cocoa.

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Chaco Canyon -

With no written language, much of what is known about the Chacoans comes from their burial sites. One found burial held 13 presumably high-ranking bodies, which DNA analysis showed were related through their mothers or grandmothers. This means power may have been passed down through the maternal line.

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Chaco Canyon -

By the 13th century, the Chacoan people began to leave for other parts of the Southwest. This was possibly due to severe drought.

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Etzanoa -

By the Walnut and Arkansas rivers, near present-day Arkansas City, once flourished a vast metropolis of more than 20,000 citizens.

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Etzanoa -

Ancestors of the Wichita Nation, the citizens of Etzanoa lived in houses shaped like big beehives, with lush gardens between the homes.

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Etzanoa -

During the cold winter months, the locals would follow the bison herds and build temporary homes while traveling.

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Etzanoa -

The people of Etzanoa had strong artisan traditions, and their trade network reached as far as Tenochtitlan in modern-day Mexico.

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Etzanoa -

In the late 16th century, Spanish conquistadors came in contact with the group living in the region. But what was a friendly encounter quickly turned. In 1601, the Spanish took hostages and the residents ran away.

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Etzanoa -

Considered a long-lost city, archaeologists believe smallpox and other diseases killed most of the original settlers.

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Spiro Mounds -

In 1933, treasure hunters stumbled across a burial chamber near Spiro, Oklahoma, which had been closed for 500 years. Inside they discovered stunning treasures.

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Spiro Mounds -

From engraved shells, pearls and beads, to brightly hued blankets and robes, newspapers dubbed the discovery the "American King Tut's tomb."

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Spiro Mounds -

Apart from the treasures, archaeologists managed to uncover an area that belonged to a prehistoric power. It equaled the size and sophistication of the Aztec and Inca.

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Spiro Mounds -

The Spiro people ruled over nearly two-thirds of what is now the US, including the eastern part of St. Louis, Moundville in Alabama, and Etowah in Georgia.

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Spiro Mounds -

From around 800 CE, the location became a permanent settlement until about 1450. At its height, some 10,000 people lived there.

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Spiro Mounds -

By 1500, the Spiro people had mysteriously disappeared. The reasons could be due to an extended drought or political infighting.

See also: Fascinating facts about the Incas

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