Ayutthaya province sits on the flat river plain of the Chao Phraya River valley. The presence of the Lopburi and Pa Sak rivers makes the province a major rice farming area. Ayutthaya was once the seat of the Kingdom of Siam, and boasts numerous ruins which indicate that at one time Ayutthaya was one of Indochina's most prosperous cities.
The Ayutthaya Historical Park is a vast stretch of historical sites in the heart of Ayutthaya city. In addition, there were many other palaces and buildings for royal visits outside the city area of Phra Nakhon Si Ayutthaya, such as Bang Pa-In Palace at Bang Pa-in and Nakhon Luang Building in the Nakhon Luang District.
Lopburi is a historically significant province, where many historical structures, artifacts, and prehistoric settlements have been discovered. Lopburi sits on the east side of the Chao Phraya River valley, between the Lopburi and Pa Sak Rivers, and is made up of plains and hills, with the Phetchabun Mountains forming the eastern boundary of the province towards the Khorat Plateau. The provincial capital Lopburi town is a relaxed placed with several well preserved historical sights to visit.