Bhutan lies eastern of Himalaya region. There are 45 named mountains in Bhutan. The climate of Bhutan varies according to the geographical segments of country. We found tropical climate in southern part, cool winter & hot summer in the central valley and severe winter & cold summers in Himalayas. The glaciers are found in the northern part of Bhutan and are considered as the main renewable source of energy in Bhutan. There are 2,624 numbers of glacial lakes found in Bhutan. Bhutan has four main river system. October to late December and February to April are the ideal time to visit Bhutan.