Gadaladeniya viharaya / temple was built by Bhuwanekhabahu IV and completed in the saaka year 1266 which is 1344 A.D. the chief architect was Ganesvaracari, a south Indian. The temple is thus essentially of south Indian designs with a Devale attached to it.

The main shrine has all the features of a Patimaghara or image house with Mandapa., Antarala and a Garbhagrha or sanctum. The Devale and the Dig-ge are to its right and project from the Mandapa, and the deity worshipped there is described as Devaraja. Identified today as Visnu. But he must have been known as Upulvan.