Dimbulagala Raja Maha Vihara is situated in the ancient city of Polonnaruwa, Sri Lanka. The Dimbulagala range houses a number of caves cut into the rock with Brahmi inscriptions over their drip ledges. This forest hermitage of medieval times and holy abode since time immemorial, home to some of the most valued fragments of early frescoes was called the Gunners Quoin by the British. This Buddhist monastery which was abandoned after the times of the Kingdom of Polonnaruwa was restored to the present status in the 1950s due to the efforts of Kithalagama Sri Seelalankara Thera.

There is also a small temple inhabited by monks at the bottom of this ancient forest hermitage. The way to the ruins is uphill along a scorching rocky-face passing strange crevices and little rock pools. The ruins of a monastery including a Chaithiya, bodhigara, poyage, dhamma saba mandapaya, ancient guard stones, and moon stones are evident. The ruins are enclosed by a stone parapet with four cardinal entrances, immediately outside was a pokuna (bath) and a stone bridge. The jungle path leading further up leads to the Akasa Chaithiya on the summit of Dimbulagala, passing ancient caves of the forest hermitage. One such imposing rock formation allowed the wattle and daub walls to be built dividing the cave into many rooms including a little verandah as well. Further up are the curative waters of the famed Namal Pokuna, and the maravidiya caves.