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On the flattened top of Doi Tong, next to the Phrathat Doi Tong temple, is the curious City Pillar of Chiang Rai.
Chiang Rai's new City Pillar, erected in 1988
Most major Thai cities have a City Pillar, called Lak Muang in Thai, although in many cases they have been erected in recent times. The pillar usually marks the center of town, and all distances from a city are measured from the pillar. It is always driven into the ground on a date and time deemed auspicious by astrologers. In the case of Chiang Rai, that was 26 January 1263.
Although one guidebook claims that the original City Pillar for Chiang Rai is in the grounds of Wat Phrathat Doi Tong, the temple next to the new pillar, it's actually in Wat Klang Wiang. Since Klang Wiang means 'center of town' in the northern dialect and the temple is nearer the center of old Chiang Rai than Doi Tong, I suspect that this is really the original City Pillar.
The new City Pillar was constructed in 1988, exactly 725 years after the original city founding. The new Pillar sits on a raised platform formed by eccentrically placed circular platforms. The phallic pillar is surrounded by a 'forest' of 108 stone phalli that radiate out from the central pillar. “Rough Guide” referred to Chiang Rai's City Pillar as a "phallic Stonehenge."