Khas and Mongoloids populate the hilly areas of Nepal, while the Madhesis, a diverse group live in the southern plains. The indigenous Tharu people are also among the early settlers of the Terai region. The Himalayas are sparsely populated above 3,000 m (9,800 ft), but north of the mountains, in central and western Nepal, ethnic Sherpas and Tamangs inhabit high, semi-arid valleys. The Kathmandu Valley, in the middle hill region, constitutes a small fraction of the nation's area but is the most densely populated, with almost 5 percent of the nation's population.