Pyramid is the oldest infrastructure in the world. It is situated in Mishor(Egypt). It is also world heritage site. We know the history of their king from Pyramid.
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 BCE–2611 BCE) 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.