Ang Ka Luang Nature Trail was surveyed and designed by Mr. Michael MacMillan Walls, a Canadian volunteer biologist who devoted to his work and died from a heart attack on this mountain. This trail is 360 metres long, passing through wet and cold areas in a lush valley. Forest above 2,000 metres is covered with lichens and wild orchids. Indigenous plants that needs a high level of nutrition, organic deposits, and rare species of birds are seen along the trail.
There are more nature trails on Doi Inthanon, each providing different views of the diversity of plants, reforestation, the importance of tributaries, the origin of caves, hilltribe agriculture, and birdwatching. Walking trails range from 1 to 8 kilometres. Each trip needs approval from the Chief of the National Park and a trekking leader is needed. The service is obtained at the Park Office at Km. 31.