The Great Pyramid of Giza is one of the great architectural marvels of history, but how the ancient Egyptians were able to haul the massive blocks into place — some from more than 500 miles away — has become a beguiling historical mystery. Theories abound, including wild postulations about ancient alien encounters, but little documentation has been uncovered that could finally put the matter to rest. That is, until now.

Archaeologists have uncovered an ancient papyrus in the ancient port of Wadi al-Jarf, on the Red Sea, that appears to be a firsthand account of the construction of the Great Pyramid. The documents of note are contained within a diary of a man named Merer, an official known to have been involved in the planning of the architectural wonder, reports Newsweek.

At more than 4,500 years old, the documents are among the oldest papyri ever found. Given their content, they might represent one of the greatest discoveries in Egyptian archaeology in recent history.

If Merer's account is authentic — and there's no reason at this time to doubt it — then the Great Pyramid's massive stones were apparently ferried via canals right up to the foot of the structure. Given that the banks of the Nile River are currently several miles from Giza, this means that an elaborate canal system had to be built specifically for the purpose of building the pyramids. This isn't an outlandish idea, given that ancient Egyptians were masters of canal building, irrigation, and otherwise redirecting the Nile to suit their needs. Still, the finding demonstrates the remarkable engineering capabilities of these ancient people.

Since the discovery of the papyrus, archaeologists have corroborated Merer's account by also unearthing a buried waterway hidden beneath the Giza plateau, as well as a ceremonial boat at the foot of the pyramids.

The findings, detailed in a new documentary titled "Egypt's Great Pyramid: The New Evidence," aired recently on British television's channel 4, and can be viewed online here.