Wat Phra That Doi Tung is popularly thought to be the site of the first chedi constructed in the Lanna Kingdom. According to legend, King Achutarat of Chiang Saen established it in the year 911 to enshrine a collar-bone relic of the Buddha brought from India. He demarcated the site by having numerous long flags (known as tung) raised atop the mountain (doi), which is why the site is known as Doi Tung (Flag Peak).
Access to the mountain is possible via a long and winding road that runs 18 kilometers along the mountainside. The road is kept in good repair since it was also used by the Princess Mother, who died in 1995, to access a palace that is also built on the mountainside. The chief objects of interest at the temple are a pair of chedis that are thought to date to the original construction, though they were renovated in the 1960s. However, at the time of the author's visit in March 2008, the chedis appear to have been moved and replaced with new chedis that do not maintain the appearance of the originals.