An Egyptian cemetery that archaeologists have been studying for decades apparently holds more than a million mummies, though where exactly all these burials came from remains a mystery, according to new research.

The remains of one mummified child, estimated to be 18 months old at the time of her death, were the most recent unearthing from the site, literally making her one in a million. She reportedly entered her final resting place in Fag el-Gamous cemetery - which means "Way of the Water Buffalo," after a nearby road - over 1,500 years ago. This was during a time when the Roman or Byzantine Empire controlled Egypt, from the 1st century to the 7th century AD.

"We are fairly certain we have over a million burials within this cemetery. It's large, and it's dense," Project Director Kerry Muhlestein, from Brigham Young University, told Live Science.

With so many deceased buried in one place, you might assume that they were all of great importance. But archaeologists say that this cemetery was not a burial ground for kings or royalty. These million people were often laid to rest without grave goods and even sometimes without coffins - both which would have been signs of some significant rank.

And though some may describe the dead as mummified, for many of them their internal organs were rarely removed. Instead the region's arid environment was responsible for their mummification.

Despite their low status and limited wealth, the excavation team did find some diamonds in the rough, so to speak. Among the remains were beautiful items including linen, glass, and even colorful booties designed for a child.

"A lot of their wealth, as little as they had, was poured into these burials," Muhlestein said.

As for the recently discovered mummified child, researchers found the body wrapped in a tunic and wearing a necklace, with two bracelets on each arm.

Experts are still trying to figure out just why such a large cemetery was set up at the site - the nearby village would have been too small to warrant it, and the nearest large town had it own cemetery.

"It's hard to know where all these people were coming from," Muhlestein told Live Science.

"We cannot determine whether the large number of burials in one shaft-tomb represented a family burial, opened repeatedly as different members of the family died (both children and adults were buried in the multiple-burial tombs), or whether some catastrophe in the village or family resulted in a mass common burial effort," Wilfred Griggs, from the Religious Studies Centre at BYU, wrote in an earlier paper on the site.

Once researchers create a database of all the excavated mummies, revealing certain burial patterns in the area, they hope to shed some light on this ancient mystery.

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