Wat Umong  is one of our favourite temples in Chiang Mai. Its an especially magical place just after the rainy season has ended, around early October or November.
Wat Umong is unique in many respects. For one, its built in the foothills of Suthep mountain and is still heavily forested. But the most unique feature of the temple are the tunnels which give the Wat its name.
The temple and its tunnels were built in the late 14^th century. On a level open space, a large artificial mound was built and then criss-crossed with tunnels. The legend is that the temple was built like this for a highly regarded monk who was nonetheless a little crazy. The somewhat maze-like tunnels kept the mad monk from wandering off.
The monastery was later abandoned and wasn't used again until the 1940s. The long disuse is probably what accounts for the overgrown atmosphere of the temple. That's why the temple is so great to visit right after the rains have gone. The brick walls of the mound are covered with moss and small plants. Other stone works are covered in moss and vines.
At one end of the mound is the temple's chedi, reachable by a short stairway to the left of the tunnel entrances. The main "bell" section of the chedi is mostly covered in thick vines, giving a strong sense of decay even though the structure of the chedi appears sound. When we were last here in early January 2003. It appeared that the chedi had been opened and the relic inside removed. A curious little ad-hoc alter had been set up on the base of the chedi right in front of the rough opening of the chedi. The alter consisted of many tiny Buddha images as well as other offerings, apparently left by many people.
A trail leads from the chedi across the roof of the mound and down the other side. Just beyond the far edge of the mound is a rather  emaciated seated Buddha image. This style of Buddha image was in style for a short time hundreds of years ago, but today there are very few examples of it still in existence.
The path down winds through the monk's cells and other out-buildings, then back around to the front of the mound. Just as the path turns back towards the main tunnel entrance is a curious collection of Buddha heads and other relics from various temples. Apparently, when people run across such relics they bring them here. Many of the stone heads were probably stolen from ancient temples somewhere in Southeast Asia and for some reason were not sold on the international art market.
If you continue on the path on past the mound and the chedi, you'll eventually come to a small lake with many fish, birds and other wildlife.