This sacred place is in the Rajagalatenna village in Uhana District Secretariat Division of the Ampara District in  the Eastern Province. In the past Rajagala known as Rassahela was one of  the premier monastic complexes in Sri Lanka that emerged since the advent of Arahant Mahinda.

The earliest inscription found at Rajagala names the place as “Dhana Tisa Pavata”. However an inscription scribed later, refers to it as  “Ariya Araka Girikubilapi Tisa Pavata Maha Vahara” which when translated reads as the Ariyakara Girikumbhilavapi Tissa Pabbata Vihara. In another inscription of King Mahinda II found in the sacred area identifies the temple as Arittara Vehera. In the great chronicle Mahavamsa it is said that when  Prince Lajjatissa was the ruler at Dighavapi, a temple by the name Girikumbhila had been built.

The discovery of places where stone implements were made in and around Rajagala, illustrates that the area had been inhabited from the prehistoric times. The mountain, particularly its  western slopes and the rock face of northern side of the range are dotted with hundreds of caves with drip-ledges. This shows that the monastery which originated in the 3rd c B.C. had been in use for a number of centuries.

Hundreds of buildings comprising dagobas, image houses, refectories, monastic buildings, ponds and promenades are visible on all sides of the temple complex. A breached reservoir which supplied water to the temple is seen on the western slopes of the mountain.

A host of rock inscriptions belonging to various periods are found here. Among them are a large number of drip-ledged inscriptions on caves. The rock inscription regarding the Arahant Mahinda Thera is the most valued inscription of archaeological interest found in this sacred area. The mention of the names of Theras Mahinda and Itthiya in the inscription confirms the advent of Thera Mahinda to Sri Lanka as described in the ancient chronicles.

Of the ruins found at Rajagala are a half completed standing Buddha image, a water spout and the two massive stone bowls associated with it. The water spout is yet functional. The guard stone depicting a guardian supporting a filled vessel in his hands, the gurdstone with the king and the queen cobras are rare artifacts found at Rajagala.

A cave with a door frame made of stone jambs is found in good preservation  on the rock-ledge above the two massive stone bowls.

A large number of primary cave paintings of an unknown period and some wall paintings of the Anuradhapura period could be seen in this sacred area.