The largest known earthwork was built in America, known as Cahokia Mounds. The site is a large temple mound in Illinois that was built by prehistoric people. So, the civilization fell into decline and was abandoned, eventually. However, while it was hustling and bustling with life, it was known to be perhaps the best one in North America. Understandably, this is how civilizations usually die out; they run out of natural resources and eventually get engaged in self-defeating wars to the point where they become non-existent.
Cahokia Mounds And Its Civilization
The sprawling city complex was the pride of its rulers. It covered nearly 4000 acres of land. The central plaza alone was more than 4 acres! The city at least had to have around 120 temple mounds for the purpose of living spaces, tombs, sacred ceremonial sites, ball courts, and meeting centers.

Dirk/Pexels | Cahokia Mounds civilization happened to be the best one of its time, and it also remains to be the largest earthwork ever done in America
Archaeologists believe that the people of this town seemed to worship its hereditary rulers in life and death. At only a little distance from the Monks Mound stands Mound 72, which goes as high as 7 feet; it is where archaeologists discovered the remains of a man. The body was laid on a platform and was covered with nearly 20,000 conch-shell disk beads that are found in the Gulf of Mexico. The beads were said to be placed in the shape of a falcon that was set beside the head of the man.
Below the body of this man laid another body. Only they were separated by shells. Also, around these two bodies, there were other human remains as well, which were assumed to be people who would’ve been killed for accompanying the entombed men in the afterlife. What is disturbingly baffling is the fact that nearly all these bodies, remains of around 53 females, all aging from 15 to 30, were found.

asap jpeg/Pexels | Study shows that all of these women were strangled to death.
What Will The End Of Our Civilization Look Like?
Arnold Toynbee is a historian who believes in the philosophy that civilizations commit suicide – they are not murdered. They fail to figure out and fix a crisis and cause their own erasure in the process. He also states that when our civilization will collapse, it will be ginormous in size. Even though the collapse patterns will be extremely similar to those of collapses in the past, the difference will be in the size, and there will be no escape from it.

Tim Mossholder/Pexels | Our civilization will meet a boundless catastrophic end
Here's to hoping this is another scientific finding that gets disproven. Only time will tell.
Until then, be responsible citizens!