Wikipedia
The Ruwanwelisaya is a stupa in Sri Lanka, considered a marvel for its architectural qualities and sacred to many Buddhists all over the world. It was built by King Dutugemunu c. 140 B.C., who became lord of all Sri Lanka after a war in which the Chola King Elara, was defeated. It is also known as Mahathupa, Swarnamali Chaitya, Suvarnamali Mahaceti (in Pali) and Rathnamali Dagaba.
This is one of the Solosmasthana (the 16 places of veneration) and the Atamasthana (the 8 places of veneration in the ancient sacred city of Anuradhapura). The stupa is one of the world's tallest monuments, standing at and with a circumference of . The Kaunghmudaw Pagoda in Sagaing, Myanmar is modeled after this stupa.
The stupa was an ancient ruin in the 19th century. After fundraising efforts by Sinhalese bhikkhu, the stupa was renovated in the early 20th century. The Ruwanveli Seya Restoration Society was founded in 1902 and the final crowning of the stupa took place on 17 June 1940.
The largest Stupa after Ruwanwelisaya was build in was the Kotmale Mahaweli Maha Seya. This stupa took 33 years and 3 months to complete.