Jethawana Stupa was built by king Mahasena in 276 – 303 AD in Mahavihara premises. At the time of construction, the stupa was third largest building in the world after two Pyramids in Egypt. Mr. Emerson Tenant a British engineer and a historian, in the early 19th century stated that, out of the bricks used to build Jetawanaramaya stupa, a wall with 3ft high and one foot width could be built from London to Edinburgh. A marvel of Sri Lankan ancient architecture is still remaining as the largest brick building in the world. Original height was 400ft and present days 372ft and diameter 367ft and foundation is 28ft. Jetawana Stupa shows the architectural and engineering skills of the ancient Sinhalese people which was not surprised by any other civilization.