Doi Chiang Dao rises dramatically above the surrounding plain, wrapped in a thick coat of tropical forest. This jungle wonderland is one of Thailand's top spots for birders, with more than 300 resident species. It's a steep two-day hike to the summit, which offers spectacular views over the surrounding massifs, and mountain is one of the best spots in the world to see the giant nuthatches and Hume's pheasants. Treks can be arranged with guesthouses in Ban Tham; expect to pay around 2400/4600B for one/two days.
If you just want a taste of the marvellous scenery, take a right at the junction just before the cluster of lodges at Ban Tham and follow the gorgeously scenic, winding mountain road that climbs to the ridge through the forest. This is a challenging ride and you'll need transport with sufficient power to handle the gradients.