AYUTTHAYA.. The ancient city of Ayutthaya, or Phra Nakhon Si Ayutthaya, was the capital of Siam for 417 years, and remains one of Thailand's major tourist attractions. Founded by 'King U-Thong or Ramathibodi I'in 1350, the city possesses left behind when the Thais were forced southwards after being sacked by the Burmese in 1767. ....................................