Wat Chaiyo Worawihan or Wat Ket Chaiyo is located on the West Bank of the Chao Phraya River, approximately 18 kilometers away from Amphoe Mueang Ang Thong, on Ang Thong Sing Buri route. This is the second-class royal monastery. Formerly it was a small ordinary temple constructed in the Ayutthaya period with the unknown building date.
Later in the reign of King Rama IV, this temple was noted when Somdet Phra Phutthachan (To Phromrangsi) a revered monk of Wat Rakhangkhositaram in Thonburi constructed a large seated Buddha image in the posture of meditation made of white plaster. In the reign of King Rama V, His Majesty the King went to worship the image and had Wat Chaiyo renovated in 1887 but the vibration from ramming piles of the wihan caused the large Buddha image to collapse.
The king then commanded to build a new large Buddha image following the pattern of the large Buddha image at Wat Kalayanamit. The new one has the lap width of 16.10 meters and the height (from radiance to feet) of 22.65 meters and was graciously named Phra Mahaphutthaphim.