The Ho Trai (Scripture Library) of Wat Phra That Sri Don Kham is a traditional Lanna wooden structure on high stilts, specifically designed to preserve ancient palm-leaf manuscripts and Phap Sa books. Historically, these libraries were built over water or raised high to protect precious documents from termites, insects, and humidity. The building is characterized by intricate wood carvings and gables decorated according to Buddhist cosmology. It once housed numerous gilded lacquerware scripture cabinets and manuscripts written in the Lanna Dhamma script. Today, many of these artifacts have been moved to the Phra Chao Phra To Museum for enhanced security and professional conservation.