The massive graveyard of nearly 70 fossilized Columbian mammoths unearthed near Mexico City has turned into ‘mammoth central.’

The number has risen to at least 200 remains since being first uncovered in 2019 by construction workers clearing land for a new airport in the town of Santa Lucia, located in the central Mexican state of Mexico State.

Archaeologists working at the site say discoveries are still being found, including signs that humans may have made tools from the bones of the lumbering animals that died somewhere between 10,000 and 20,000 years ago.

The first group of skeletons were discovered last year, but images of the findings were not released until this past May.

A mammoth exhibit is being planned in the main terminal of the new Felipe Angeles international airport in Santa Lucia when construction finishes.

As well as a vast haul of fossil remains, 15 human skulls believed to be from pre-Hispanic burials along with receptacles, obsidian and the remains of dogs were previously found at the site.

The new findings are helping experts understand what led to the demise of these massive creatures.

Along with being killed by ancient humans, the team notes that the shores of an ancient lakebed that both attracted and trapped mammoths in its marshy soil, may help solve the riddle of their extinction.

Archaeologist Ruben Manzanilla Lopez of the National Institute of Anthropology and History, referring to animals that went extinct in the Americas, said: ‘We have about 200 mammoths, about 25 camels, five horses.’

The site stretches for 12 miles and reveals man-made pits that may have been used to trap the unsuspecting mammoths, which were re-purposed as tools.

‘Here we have found evidence that we have the same kind of tools, but until we can do the laboratory studies to see marks of these tools or possible tools, we can’t say we have evidence that is well-founded,’ Manzanilla Lopez said.

Palaeontologist Joaquin Arroyo Cabrales and the team will use this site and remains to test their theories of what happened to these massive creatures – was it climate change or humans that led to their demise.

‘I think in the end the decision will be that there was a synergy effect between climate change and human presence,’ Arroyo Cabrales said.

Prior to the discovery in Mexico, North Dakota held the title for the most mammoth remains – about 61 sets of skeletons were uncovered in Hot Springs.

Mexican Army Captain Jesus Cantoral, who oversees efforts to preserve remains at the army-led construction site, said ‘a large number of excavation sites’ are still pending detailed study, and that observers have to accompany diggers and bulldozers every time they break ground at a new spot.

The project is so huge, he noted, that the machines can just go work somewhere else while archaeologists study an area.

Experts believe some of the animals uncovered at the site may be up to 35,000 years old.

The area was rich with wildlife during the era of the mammoths as it was the intersection of four separate valleys and therefore acted like a natural corridor.

Pedro Francisco Sanchez Nava, the National Coordinator of Anthropology at the INAH told local media in May: ‘Perhaps 15,000 years ago human beings noticed the passage and organised as a society to hunt them.’

Humans living in the region may have exploited this prehistoric migration path and laid traps to hunt.

Columbian mammoths had very little fur, unlike their woolly cousins which lived in frigid tundra.

The giants were up to 15 feet tall, wigged up to 22,000 pounds and had enormous tusks up to 16 feet long. They also had an estimated lifespan of around 65 years.

They are one of the last lineages of mammoth to go extinct in the world and were wiped out around 12,000 years ago.

The Columbian mammoth inhabited North America as far north as the northern United States and as far south as Costa Rica.