Sandagiri stupa was built by the regional ruler Prince Mahanaga in the third century B.C. Sandagiri stupa is 55m in height and 165m in circumference. According to the chronicles, around 12,000 Arahats have lived in the Tissa area during the life and times of King Kavantissa who, deposited the forehead relic of the Buddha in Sandagiri stupa.

 

Historical chronicles narrates that some of the various relics and gifts sent by Emperor Asoka to King Devanmpiyatissa (250-210 BC) of Sri Lanka were enshrined in the Sandagiri Stupa of Ruhuna. However, the first provincial ruler to have begun the construction of sacred places of Buddhist worship in Ruhuna was Mahanaga. Historical chronicles narrate that Buddha, in his third visit to Sri Lanka arrived at Tissamaharama and hence the ancient settlement is considered sixteen sacred locations of the island.