Wat Phra Kaeo Don Tao is Lampang's premier wat, holding the honor of being one of the few places known to have enshrined the Emerald Buddha, one of the sacred images of the Thai Kingdom. The Emerald Buddha, probably made of green jasper, is presently located in Bangkok but was originally discovered at Wat Phra Kaeo in Chiang Rai. Two years after its discovery, an elephant was recruited to bring the image to Chiang Mai for enshrinement. However, in the manner of Lanna elephants, the creature made its own choices and continuously headed toward Lampang. This was taken as an omen, and the Buddha image was instead kept here at Wat Phra Kaeo Don Tao, from 1434 to 1468, after which King Tilokaraj had it brought to Chiang Mai as originally intended.
The full name of the monastery means "The Monastery of the Emerald Buddha on the Water Jar Knoll". This name partly derives from the legend of Mae Suchada, a religiously-inclined woman living around the year 500. At that time, the area was in the midst of an unusually severe famine. One day, a monk descended from heaven and offered Mae Suchada a watermelon. When she broke it open, she found a large green gem which turned into a Buddha image through the assistance of the god Indra. Although this helped alleviate the famine, the local king grew suspicious of the monk working so closely with a woman and suspected the two of them were secretly lovers. He ordered the two executed, but the monk managed to escape (Mae Suchada was not so fortunate). Another famine subsequently ravaged the kingdom, proving the error of the king's judgement. The image in question is now enshrined at Wat Phra That Lampang Luang.
Map : https://goo.gl/maps/GYM43fuCDJhZyfoKA