Ayutthaya was a Siamese kingdom that existed from 1350 to 1767.
Wat Mahathat is perhaps the most striking of all of the temples in Ayutthaya and is located the very heart of the city. The temple was built in the early days of Ayutthaya in the late 14th century by King Borommaracha I. The temple was destroyed by the Burmese who also vandalised many of the Buddha images in Ayutthaya by lopping off the heads.
On this card novices pay respect to Buddha's head overgrown by a fig tree in Wat Mahatat.
Nobody knows for certain how the Buddha head became entwined in the roots of the tree. One theory suggests that the tree simply grew around the Buddha head during the period when the temple lay abandoned and overgrown. Another theory is that a thief moved the Buddha head away from the main temple to hide it. This may have happened in the early 1900s when it is known that one of the remaining areas of the temple collapsed and consequently led to treasure hunters digging in the area. After moving the stone Buddha head away from the ruined main temple, it is possible the thief never returned for his treasure or couldn’t move it any further beyond the walls that surround the temple. Instead, the stone Buddha head was abandoned by the wall not far from the entrance of Wat Mahathat where it can be seen today nestled in the tree roots which have grown around it. - in: http://www.thaizer.com/tourist-attractions/buddha-head-in-tree-roots-wat-mahathat-ayutthaya/