There are also several mountain passes that run through the province. One of the most famous is the Khyber Pass which links Afghanistan with Pakistan. The trade route sees a large number of trucks and lorries importing and exporting goods in and out of the region. The Babusar Pass is another mountain pass connecting the Thak Nala with Chilas on the Karakorum Highway. The Lowari Pass is another pass which connects Chitral with Dir via the Lowari Tunnel. The highest mountain pass in Pakistan is Shandur Pass which connects Chitral to Gilgit and is known as the Roof of the World. The pass is the centre of three mountain ranges - Hindukush, Pamir and Karakoram.