This seven-storey building is knowns as the palace of King Prakramabahu who has being ruling the Polonnaruwa kingdom during the 1153-1186. This palace has been called  'Sankumuppaya' as well. There is only about three floors left currently. The chronicles say that there were a thousand rooms here. At present, 55 rooms remain. During the invation of Kalinga Magha from India this palace along with many other sturcture in Polonnaruwa was destroyed.