Egyptian Pyramids

We know that construction began on the first Pyramid around 2600 BC, one of the 31 dynasties of Egyptian history during the Fourth Dynasty. Part of Egypt's Old Kingdom, the Fourth Dynasty ruled Egypt from 2613 to 2494 BC, more than 2,500 years before Queen Cleopatra.

We know the Pyramids were built just outside the ancient Egyptian city of Memphis, capital of the Fourth Dynasty and home to the Pharaohs who built them. The city's close proximity to the Nile River was useful in the transport of building materials to the site of the Giza Necropolis.

We know the Pyramids were primarily built with limestone, but granite, mortar, basalt and mud were also used in their construction. The average block weighed 2.5 tons, and many came from up to 800 km (500 miles) away by barge. How the stones were lifted into place is still being debated. Approximately 5.5 million tons of limestone were used for the Great Pyramid, which is more than ten times the weight of the Burj Khalifa, the world's tallest building.

We know the Pyramids were built as tombs for the pharaohs (or kings) of ancient Egypt to facilitate their journey to the heavens. After death, a pharaoh was mummified and enclosed in a wood coffin and stone sarcophagus. He was buried with important items for the afterlife, ranging from household goods to precious valuables. Pharaohs built pyramids not only to house their bodies, but to leave a legacy of their power.

We know tens of thousands of people built the Pyramids, although there is no way to know exactly how many. Until recently it was believed they were constructed with slave labor, but we now know that seasonal laborers worked, lived and were buried on site. One work gang inscribed their nickname on the inside of the Pyramid they built: 'The Drunkards of Menkaure.'