when were the pyramids built

The Egyptian pyramids are ancient pyramid-shaped masonry structures located in Egypt.

There are 138 pyramids discovered in Egypt as of 2008. Most were built as tombs for the country's Pharaohs and their consorts during the Old and Middle Kingdom periods.

The earliest known Egyptian pyramids are found at Saqqara, northwest of Memphis. The earliest among these is the Pyramid of Djoser (constructed 2630 BC–2611 BC) which was built during the third dynasty. This pyramid and its surrounding complex were designed by the architect Imhotep, and are generally considered to be the world's oldest monumental structures constructed of dressed masonry. The estimate of the number of workers to build the pyramids range from a few thousand, twenty thousand, and up to 100,000