Ancient Kingdom – ථූපාරාම පිළිම ගෙය-Thuparama Image House

One of the few structures with a roof made entirely of bricks is the Thuparama Image House in the old city of Polonnaruwa. These structures are referred to be "Gedige" (vaulted roof) kinds, and miraculously, the roof has remained intact for more than 900 years. This is the country's best-preserved example of Gedi-ge architecture, claims Paranavithana. The roof is roughly semicircular in shape.
Three structures of the Gedige style may be found in Polonnaruwa's ancient city. The Thivanka PilimaGe and Lankathilaka Image House are the other 2. These vaulted-roofed structures appear to have been decorated with mezzo reliefs of Ganas, building facades (Vimana), pilasters, and statues of gods, as well as Jataka stories painted on the inner walls. This architecture is fairly obvious given the Thivanka PilimaGe's state of preservation.
The constructor of this image house is likewise unknown because the original name of the building is unknown. This is said to have been constructed by Mahinda, a minister of King Parakramabahu (1153-1186), to contain the tooth relic. Another theory holds that Vijayabahu I (1070–1110) constructed this.
The interior of the shrine is little compared to the exterior scale of the building because the walls of this structure are only about 7 feet (2 meters) thick. Inside the structure is a sizable Buddha statue that is designed for seats. Today, nothing is left of this statue. According to legend, the Buddha statue's eyes were set with priceless stones, and the windows were constructed so that sunlight would reflect off the stones and illuminate the building housing the statue.

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