What is it called when two rivers join together?

When two rivers flow together and merge into one, the place where they join is called a confluence. The word also appears as "conflux." It is one of the most common features in the natural world — almost every large river is fed by smaller rivers joining it along the way, and each of those joining points is a confluence.

A confluence is not always two equal rivers meeting. Geographers describe a few different cases. Sometimes a smaller river, called a tributary, flows into a much larger one. Sometimes two streams of similar size meet and together form a new river with a new name. And sometimes a river that had split around an island simply rejoins itself further downstream. All of these count as a confluence.

One of the most striking things about a confluence is that you can often see it with your own eyes. The two rivers may carry water of different colors — one muddy and pale, the other dark and clear — because each river picks up different soil, plants, and minerals on its journey. Where they meet, the two colors can flow side by side for a stretch before finally blending, creating a clear line in the water.

This article was written using information from Wikipedia.