Phra That Sri Don Kham is a large, ancient Lanna-style octagonal pagoda located at Wat Sri Don Kham (also known as Wat Huai Or) in Long District, Phrae Province. It is believed to have been constructed around 1078 B.E. during Queen Jamadevi's journey from Lavo to Haripunjaya. The pagoda enshrines the "Phra Uratti" (the Buddha's breastbone relic). Having undergone multiple restorations, the structure currently features a concrete octagonal base supporting a bell-shaped body and a spire adorned with golden "Jangko" metal sheets. It has served as the spiritual center of the Long community for over a millennium.