Galpotha to the east of the Hatadage is ('Book of stone') which is to the side of the path and can easily be missed. According to the inscription it weight 25 tons, and was brought over 90km from Mihintale. It is in the form of a palm leaf measuring over 9m by 1.2m, over 60cm thick in places, with Sinhalese inscription praising the works of the King Nissankamalla (1187-1196 A.D.). including his conquests in India
it is the largest slab inscription of Sri Lanka..believed to have brought from Mihintale using elephants and logs.
It describes the places king visited, connection had with foreign countries, about wars and rules & regulations to be abided by even after his death.