Ruwanwelisaya is located in the Anuradhapura District of the North Central Province of Sri Lanka, was built by King Dutugemunu. It was the largest stupa ever built in Sri Lanka at that time. First, the stupa was dug seven cubits deep into the ground. Then limestone was brought in by strong men, put in the pit, cut into pieces, watered, and leveled by elephants in leather shoes. After that the stones were reinforced with a type of clay called Wedaru clay. Later, another layer of stone was placed on top of the rock, and a layer of gravel and a layer of crystal were placed on top of the layer of gravel. The stone was then coated with a type of clay called Navaneetha. Then a metal mesh with diwali glue dissolved in a chemical liquid was placed on it. It was covered with sesame oil-soaked ratsiriyal stones. Historical sources show that the foundations of the Ruwanweli Stupa were laid in this manner.
Ruwanweli Maha Seya is the abode of the relics of Lord Buddha.