South Asia contains several major rivers and mountain ranges. The long Ganges and Brahmaputra rivers originate in the Himalayas and flow across the Indo-Gangetic plain. The Indus River also flows through the region. Major physical features include the Tibetan Plateau and Thar Desert. South Asia has a variety of climates due to its size and terrain, and is affected by seasonal monsoon winds and rains. Countries in the region include India, Pakistan, Bangladesh, Nepal, Bhutan, and Sri Lanka.