One of the most photographed site in Sukhothai isWat Si Chum (Temple of the Bodhi Tree) with its 15 meters high giant seated Buddha image. An opening in the front wall allows you to discover it long before entering the building that houses it. Make sure to bring an ultra wide lens to get the whole buddha and the hole in the roof . If you come early in the morning (8-9AM) you have a good chance to see monks praying and chanting.