Stock Photo - EARTH China/Russia -- 27 Sep 2013 -- Satellite image of the Amur River ( Heilong Jiang in Chinese ) flows unfettered from Mongolia to China to Russia (forming the Chinese-Russian border), and through Russia's Far East into the Sea of Okhotsk - a journey of 4,444 kilometers (2,761 miles). It is the tenth longest river in the world, and the third longest without a dam. Confined by mountains for most of its course, the river winds across a vast alluvial flood plain in its midsection, where it grows and shrinks dramatically throughout the year. Water levels vary so much that the river's minimum recorded flow is just one percent of its maximum recorded flow. Monsoon rains cause multiple floods each year, usually in July and August - when the river can expand to 10 to 25 kilometers in width -- Picture by Lightroom Photos/NASA.