Cinematic 4K 60 fps. A river is a natural flowing watercourse, freshwater flowing towards an water. Small rivers can be referred to using names such as stream, creek, brook, rivulet, and rill. Turquoise lowland geography topography floodplain flood plain run burn beck nature drainage basin alluvial alluvium large big slow flow winter spring symmetrical and flat aerial potamic fluvial drone fly nile wide riverbed amazon yangtze floods mississippi missouri field fields yenisei angara selenge kagera volga infield danube ural dnieper don pechora fallow kama columbia amur argun dvina araguaia brown background landscape view nature natural bright true simple standard oka euphrates yukon pecos tigris negro arkansas nelson red belaya dniester lena amu darya kolyma indus rhine salween rio eyre grande elbe vilyuy niger donets darling mekong loire oder warta aras brazos vltava ottawa vistula tagus UHD 3840X2160.