Doi Inthanon is Thailand's highest mountain. Bird life and waterfalls. During the winter season the summit of Doi Inthanon is usually cool and dry. The area is renowned for mist when temperatures decline and images of the mountain’s hazy beauty have become somewhat iconic. Two large pagodas built for the current King and Queen of Thailand are situated on the mountain’s summit. Doi Inthanon Forest has been established as a National Park.