Bhutan, a Buddhist kingdom on the Himalayas’ eastern edge, is known for its monasteries, fortresses (or dzongs) and dramatic landscapes that range from subtropical plains to steep mountains and valleys. In the High Himalayas, peaks such as 7,326m Jomolhari are popular trekking destinations. Paro Taktsang monastery (also known as Tiger’s Nest) clings to cliffs above the forested Paro Valley. The King of Bhutan is known as the "Dragon King". Bhutan is also notable for pioneering the concept of gross national happiness. The country's landscape ranges from lush subtropical plains in the south to the sub-alpine Himalayan mountains in the north, where there are peaks in excess of 7,000 metres (23,000 ft). The highest mountain in Bhutan is the Gangkhar Puensum, which is also a strong candidate for the highest unclimbed mountain in the world. There is also diverse wildlife in Bhutan. The climate in Bhutan varies with elevation, from subtropical in the south to temperate in the highlands and polar-type climate, with year-round snow in the north. Bhutan experiences five distinct seasons: summer, monsoon, autumn, winter and spring. Western Bhutan has the heavier monsoon rains; southern Bhutan has hot humid summers and cool winters; central and eastern Bhutan is temperate and drier than the west with warm summers and cool winters.