The Ruwanweli Maha Seya, also known as the Maha Thupa, is a stupa in Anuradhapura, Sri Lanka. Two quarts or one Dona of the Buddha's relics are enshrined in the stupa, making it the largest collection of his relics anywhere. It was built by Sinhalese King Dutugemunu in c. 140 B.C., who became king of Sri Lanka after a war in which the Chola King Elāra (Ellalan) was defeated. It is also known as Swarnamali Seya, Svaṇṇamāli Mahaceti and Rathnamali Seya.

In Buddhism, a stupa is a mound-like or hemispherical structure containing relics that is used as a place of meditation.