The United States is under 250 years old, but some of its maximum archaeological sites are older than Vikings sailors, the Roman empire and the pyramids.

Many assistance say how the first humans arrived here in North America. It is a mystery precisely how and when other people arrived, although it is widely believed that they crossed the Bering Strait at least 15,000 years.

“As we return to time, while we have other people who are getting smaller and smaller, locating those positions and interpreting them becomes increasingly difficult,” said archaeologist Kenneth Feder a Business Insider. He is “ancient America: fifty archaeological sites to see through yourself. “

Some sites, such as White Sands and Cooper’s Ferry, have skeptics about the precision of their age. However, they give a contribution to our understanding of some of the first Americans.

Many of those puts are open to the public, so you can see the old story of yourself.

“Where are they coming from?” Feder said. “They’re not parachute dropping in New Mexico. They must have come from somewhere else, which means there are even older sites.” Archaeologists simply haven’t found them yet.

While visitors can soak in the sight of the eponymous white sands, the footprints are currently off-limits.

In the 1970s, archaeologist James M. Adovasio sparked a controversy when he and his colleagues suggested stone tools and other artifacts found in southwestern Pennsylvania belonged to humans who had lived in the area 16,000 years ago.

For decades, scientists had been finding evidence of human habitation that all seemed to be around 12,000 to 13,000 years old, belonging to the Clovis culture. They were long believed to have been the first to cross the Bering land bridge. Humans who arrived in North America before this group are often referred to as pre-Clovis.

At the time, skeptics said that the radiocarbon dating evidence was flawed, AP News reported in 2016. In the years since, more sites that appear older than 13,000 years have been found across the US.

Feder said Adovasio meticulously excavated the site, but there’s still no clear consensus about the age of the oldest artifacts. Still, he said, “that site is absolutely a major, important, significant site.” It helped archaeologists realize humans started arriving on the continent before the Clovis people.

The dig itself is on display at the Heinz History Center, allowing visitors to see an excavation in person.

One site that’s added intriguing evidence to the pre-Clovis theory is located in western Idaho. Humans living there left stone tools and charred bones in a hearth between 14,000 and 16,000 years ago, according to radiocarbon dating. Other researchers put the dates closer to 11,500 years ago.

These stemmed tools are different from the Clovis fluted projectiles, researchers wrote in a 2019 Science Advances paper.

Some scientists think humans may have been traveling along the West Coast at this time, when huge ice sheets covered Alaska and Canada. “People using boats, using canoes could hop along that coast and end up in North America long before those glacial ice bodies decoupled,” Feder said.

Cooper’s Ferry is located on traditional Nez Perce land, which the Bureau of Land Management holds in public ownership.

In the early 1980s, former Navy SEAL Buddy Page alerted paleontologists and archaeologists to a sinkhole nicknamed “Booger Hole” in the Aucilla River. There, the researchers found mammoth and mastodon bones and stone tools.

They also discovered a mastodon tusk with what appeared to be cut marks believed to be made by a tool. Other scientists have returned to the site more recently, bringing up more bones and tools. They used radiocarbon dating, which established the site as pre-Clovis.

Located in the center of Oregon-South, the caves seem to be a piece of the puzzle that indicates how humans have the continent thousands of years ago.

The Federal Land Management Office owns the land where the caves are located, and are signed at the beginning of historical places.

The in Alaska with the oldest evidence of human housing is Swan Point, in the region of the central-east of the State. In addition to the 14,000 -year -old teams and homes, gigantic bones were discovered there.

The researchers who examine the site began to realize that the artifacts discovered on the site belonged to other cultures. Clovis’s problems are larger than Folsom flutes, which were first discovered in another archaeological site of New Mexico.

Archaeologists discovered the bones of the child in 2013. Local teams call it xach’ite’anenh t’eede gay, or dawn girl. Genetic tests revealed that the 11,300 -year -old baby belonged to a Amerindian population in the unknown past, the ancient Beringios.

The artifacts that the equipment left implies that the site has been used and for many years and was an assembly point for trade. People have brought equipment and rocks at 800 miles away. The remains of deer, fish, frogs, caimanes, nuts, grapes and other foods have given archaeologists a review of their nutrition and daily life.

It is a complicated walk to succeed in pictograms (and the NPS warns that it can be dangerously hot in summer) but it is seeing in person, Feder said. “These are artistic geniuses,” he said about artists.

Located in the Navajo nation, Celly Canyon has magnificent perspectives of the desert and thousands of years of human history. Centuries ago, the ancestral teams and Hopi have planted cultures, created pictograms and built cliff houses.

More than 900 years ago, the other town of Puebloan built the White House, which bears the name of the shadow of their clay. Its upper floors are sitting in a sandstone cliff, with a transparent fall of the windows.

The other people of Navajo, also known as Diné, still live in the Congo Canyon. Diné Alastair journalist Lee Bitsóí recently wrote about some of the sacred and taboo areas. They come with Tsé Yaa Kin, where archaeologists have discovered human remains.

In early 1900, two shaped the Leling Association of Coliff Coliff, hoping to maintain the ruins in the state region of the Southwest. A few years later, President Theodore Roosevelt signed an invoice that designates the Green Mesa as the first national park aimed at “maintaining the works of man. “

The Mesa Verde National Park has a large number of homes, adding the Palais de Falaises. It has more than one hundred rooms and approximately two dozen kivas or ceremonial areas.

With the help of dendrocronology or trees dating, archaeologists learned when the ancestral people built some of those structures and that emigrated outside the doors of the region through the years 1300.

Cahokia called one of the first cities in North America. Not far from St. Louis existing, around 10,000 to 20,000 people lived in dense colonies about 1,000 years ago. The important buildings were sitting on the most sensible giant mounds, which the Mississippiens built by hand, The Guardian reported.

The population built posts of posts, which an archaeologist called “Woodhenges”, as a type of calendar. In the solstices, the sun rises or lies aligned with other mounds.

After a few hundred years, the population of Cahakia decreased and disappeared by 1350. Its largest mound remains, and the safe facets were rebuilt.

Presented in a limestone cliff in Camp Verde, Arizona, this is an apartment, not a castle, and is not connected to Sovereign Aztec Montezuma.

The other people of Sinagua have designed the construction of five stories and 20 rooms around 1100. It is curved to adhere to the herbal line of the cliff, which would have been more complicated than simply making a correct construction, Feder said.

“These other people were architects,” he said. “They had a feeling of beauty. “