Wat Phra Singha

The purple jade Buddha is the reason to come. You see plenty of gold and plenty of emerald-green replicas around northern Thailand, but a Buddha carved from purple jade is a genuinely odd and lovely thing, and it sits in a working temple rather than a ticketed attraction.

The rest is classic Lanna: gilded rooflines, carved timber, a courtyard that stays quiet even though you're inside Chiang Rai city. Founded in the 14th century under King Pra Chao Maha Proma, so there's real age here, though what you're walking through has clearly been cared for and restored over the centuries rather than left to crumble. My advice is to go early. Doors open at seven, the morning light on the gilding is worth the alarm, and you'll share the grounds with people who are there to pray rather than photograph. Give it half an hour, more if you sit. It pairs well with the White Temple or the Clock Tower on the same day, since it's small and central.