Ayutthaya is the former capital of Siam, from 1350 until mid-18th century, and at one time was one of the largest cities in the world. The capital was relocated to Bangkok in 1768 when the Burmese army destroyed much of Ayutthaya. Today tourists needn't imagine too much to experience splendour of the old capital as many of the enormous structures are still there, and the ruins of Ayutthaya have been designated a UNESCO World Heritage Site. Multiple buses (a trip that takes a bit over an hour) and trains arrive daily from Bangkok and a boat up the Chao Phraya River to Ayutthaya can be organised through travel agencies. Although many organised tours in Thailand can be a frustrating experience, a tour guide here can give some fascinating history to the already impressive wats. This is an easy way to experience some of the ancient history of Siam as Bangkok is relatively new.
Address: At the junction of the Chao Phraya, Lopburi and Pa Sak rivers