10 of the Oldest Cities in the World:3. Rey. Iran

Historians attribute the founding and building of Rey to ancient mythological monarchs. At some point was the seat of the dynasty of a Zoroastrian leader and to this day it is a sacred Zoroastrian city. Rey is within the Greater Tehran metropolitan area, and was first settled 8,000 years ago, though it has likely been continuously occupied for about 5,000 to 6,000 years. The city retains a wealth of historical monuments, such as the 5,000-year-old Cheshmeh Ali hill, the 3,000-year-old Gebri castle and Shah Abbasi caravanserai.