Rivers are the water paths that rain and snow follow from higher elevations to lower elevations until they reach the ocean. Sometimes they end in a lake or another river, but gravity ensures that water flows to a lower level, like sea level.

Rivers are the water paths that rain and snow follow from higher elevations to lower elevations until they reach the ocean. Sometimes they end in a lake or another river, but gravity ensures that water flows to a lower level, like sea level.