Wat Phrathat Doi Suthep, Chiang Mai
Although this temple is a main tourist attraction and is generally busy, it is definitely worth a visit.
Located on a mountain 15km outside of Chiang Mai, you can feel the air temperature drop as you leave the city, which is always a good thing in Thailand!
Food and souvenir stalls line the way up the stairs to the temple entrance, with the vendors supplying multiple photo opportunities. The temple itself is of course gorgeous, as most temples in Thailand are, but also make sure you go to the viewpoint up there as the view of Chiang Mai from up in the clouds is pretty special.