This temple originally lay in a fortified square beyond Chiang Mai walls. Legends tell that King Ku Na invited the venerable Sumana Thera, a very pious monk from Sukhothai to bring the Buddhism of Sri Lanka to Chiang Mai.The King offered him the royal flower garden (Suan Dok) as a place to build a temple. The temple was established in 1371.When Sumana Thera was living in Sukhothai, he had a vision which showed him where to find a very holy relic that had long been buried near the city. When the relic was unearthed, miraculous illuminations took place confirming its power. These miracles did not repeat themselves for the King of Sukhothai, who left the relic in the care of the monk.Thus when King Ku Na invited Sumana Thera to Chiang Mai, the monk brought the holy relic with him. When the relic was about to be enshrined at the temple, he found that the relic had split into two pieces. One of these pieces was kept at Wat Suandok, and the other was buried at Wat Phrathat Doi Suthep.

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