A landlocked mountainous country with plains in the north and southwest, Afghanistan is located within the heart of Asia, and is part of the US-coined Greater Middle East Muslim world. It has been the centre of many powerful empires for the past 2,000 years. Despite having numerous rivers and reservoirs, large parts of the country are dry. The endorheic Sistan Basin is one of the driest regions in the world. Aside from the usual rainfall, Afghanistan receives snow during the winter in the Hindu Kushand Pamir Mountains, and the melting snow in the spring season enters the rivers, lakes, and streams.