The gridiron layout of a town or city is not new. It is, in fact, "the most pervasive city design on earth" and can be found in "Italy and Greece, in Mexico, Central America, Mesopotamia, China Japan." It can be found in the Old and New Kingdoms of Ancient Egypt, and in Mohenjo-daro in the Indus Valley in 2154 BCE with a population of 40,000 people, where many historians claim it was invented, and from where it may have spread to Ancient Greece. The Greek city of Miletus was rebuilt after destruction by the Persians on a grid plan, with Hippodamusoften called "the father of European urban planning"as the local originator of the rectilinear grid system for the city centered on the "agora", a concept he probably did not invent, but had heard about from elsewhere. Hippodamus went on to spread the grid to Piraeus, Rhodes, and other cities in Greece.