My wife and I visited the Bua Thong Waterfalls ("Sticky Waterfalls") while in Chiang Mai for our honeymoon, and it was a great afternoon activity to cool off from the heat. The waterfalls are beautiful to look at and easily climbable thanks to the calcium deposits on the rocks from the spring water flowing over them. The little cafe/ restaurant at the entrance to the waterfalls offers tasty dishes at reasonable prices, too!