After the defeat by the Tamil invaders on the same year he came to the throne king Walagamba (103 BC) has hidden in a place called “Silasobbha Khandaka” and after defeating the Tamils and regaining the throne he has built this stupa by the same name. This stupa is similar to Thuparama which is the first stupa built after Buddhism was brought to the country in the 250 BC. This stupa too has had a magnificent vatadage surrounding the stupa. There are indications of 88 stone pillars have supported the roof of the vatadage. Today only few remains out of these.
The best of this vatadage architecture can bee seen in Madirigiriya.