Founded in 1350, the city of Ayutthaya is claimed as a Unesco World Heritage Site. Between the 14th and 18th centuries it grew to at one point be the biggest city in the world. The city was attacked by the Burmese army in 1767 and was burned to the ground which forced all of the citizens to leave the city. The city was never rebuilt and is now an important historical site. Present day Ayutthaya is now built around the remaining ruins and is a reminder of the great city that once stood there.