Scientists have already excavated more than 1,700 mummies, preserved by the hot dry desert in the Faiyum region of Egypt about 60 miles (96km) south of Cairo. But those leading the work believe their could be up to a million similar bodies buried in shafts cut into the limestone rock that are at times up to 75ft (22.9 metres) deep.
It is thought that the mummies were buried around 1,500 years ago, between the 1st and 7th Century AD, when Egypt was controlled by the Roman and Byzantine Empire. Unlike many famous mummified remains discovered in Egypt, these were found in mass graves and appear to be ordinary citizens rather than royalty or other important figures.
Yet scientists are baffled about where the huge numbers of mummies came from – the remains of a nearby village is too small to warrant such a large cemetery and the nearest town, named Philadelphia after King Ptolemy II Phiadelphus, has its own burial sites.
Archaeologists have also uncovered a bizarre range of mummies, including one man who is more than seven feet (213 cm) tall. They have also discovered that the mummies appear to be clustered together by hair colour, with those with blond hair in one area and all of those with red hair in another.
Professor Kerry Muhlestein, project director of the excavation at Brigham Young University, in Utah, said: ‘The cemetery is densely populated. ‘In a square that is 5 x 5 meters across and usually just over 2 meters deep, we will typically find about 40 burials.