Large protohistoric and early historic site in the lower Chao Phraya valley of central Thailand. It is thought to have been the capital of the state of Dvaravati for a while. According to local tradition, it is the oldest city in Thailand - said to be more than 2,000 years old - and was visited by the Buddha. Artifacts have been found there dating from the 6th century AD. Phra Pathom, the highest stupa in Thailand, rises to 380 feet (116 m).