The Taklamakan is one of the largest sandy deserts in the world, ranking 18th in size in a ranking of the world's largest non-polar deserts. It covers an area of 270,000 km2 (100,000 sq mi) of the Tarim Basin, 1,000 kilometres (620 mi) long and 400 kilometres (250 mi) wide. It is crossed at its northern and at its southern edge by two branches of the Silk Road as travelers sought to avoid the arid wasteland.