Corbis This gilded Greco-Roman mummy was one of the first found in the ancient necropolis

But three years ago, archaeologists literally stumbled upon an opportunity to explore this period after an antiquities guard riding on a donkey accidentally punched through the roof of a tomb in the desert oasis of Bahariya. As he peered inside with a flashlight, a glimmer of gold promised this was no ordinary hole in the ground.

After only a month of preliminary excavations last year, Egyptologists uncovered a trove of 105 well-preserved mummies dating back to the Greek and Roman periods of Egyptian history. The scientists also identified more than 100 other tombs over a two-square-mile area situated some 200 miles southwest of Cairo. They estimate the site contains more than 10,000 mummies, making it the biggest mummy cemetery ever found.

Indeed, the ancient necropolis is believed to be so extensive that Egyptian archaeologists call it the "Valley of the Mummies." With further excavations now underway, they predict the site eventually will take its place beside the tomb of King Tutankhamen as yet another extraordinary window into the country's past.

If that celebrated discovery taught the world about the wealth and splendor of Egypt's pharonic period, archaeologists hope their findings in Valley of the Mummies will help fill out the more murky Greek and Roman era of Egyptian history. That era, which began with Alexander's conquest of Egypt in 332 B.C. and lasted until the second century A.D., is only now beginning to be understood.

Corbis Many of the 105 mummies were bedecked in the metal of the ancient gods: gold

But the site is already yielding fascinating clues into this period of cultural transition, as Egypt absorbed the arts and gods of her Greek and Roman conquerors.

During pharonic times, only the richest and most powerful figures were mummified. But the discoveries in Bahariya suggest that the practice seemed to have become commonplace among the middle class during the Greco-Roman era. In that sense, the Bahariya cemetery may have been the ancient Egyptian equivalent of New York's Forest Lawn.

For centuries, Bahariya flourished as an oasis known for making wine. Nearby is a newly excavated temple to Alexander the Great, who is believed to have traveled through the area.

The mummies appear to reflect both the good economic times, as well as the mixture of Greek, and later Roman, influences with the rich Egyptian culture. Some are elaborately encased in gold, indicating wealth. Some are encased in pottery shells, suggesting a more middle class station, while the poor are simply wrapped in linen — like the mummies in Hollywood horror films.

Corbis Many of the crypts in Bahariya are similar. You walk down a few steps into a narrow room with shelves lined with mummies

The paintings on the more elaborately encased mummies reflect Greek culture's influence on the Egyptians. As with classic Greek sculpture, the hair is a profusion of curls and the faces have long, aquiline noses, strong chins and expressive mouths. Some female figures have golden breasts tipped with jewels. Yet the encasements also depict various Egyptian gods and symbols.

The manner in which the dead were prepared also appears to confirm that mummification was waning as Christianity began to spread throughout Egypt. In pharonic times, the internal organs of the dead were placed in jars and buried alongside the mummified bodies. No such jars were found in Bahariya. Neither were the wooden cases and coffins that were used in earlier eras.

Though coins and other artifacts found with the mummies all suggest the dead are from the first and second centuries A.D., archaeologists are still working to determine precisely who these people were in life and how they died. To assist them in finding these answers, the scientists are using such forensic techniques as X-rays and DNA analysis. But some of the details painted onto the mummies' breastplates continue to be baffling.

One of the pictures shows human figures, their heads crowned with what look like halos. Who are they? Could they have been early Christians? Another picture shows a man running. Could he be the Greek god Hermes, accompanying the dead to the underworld?

As the archaeologists unearth and examine more mummies, they're hoping the dead may give up their secrets about Egyptian life during the age of the Ptolemies and beyond.