With river deltas providing rich farm land plus access to other places via the river and what the river connects to, deltas around the world have been important sites for human settlements.

On a recent trip, I found a spot where water flows down a bluff before heading for a large lake. Here is what it can look like:

The image shows how even a small flow of water, strengthened by recent rains, can push sand in a distinctive pattern. With enough water, the delta would grow and the stream would cross the beach and make it to the lake.

Even in a world devoted to technology and online activity, how many major cities and nations continue to rely on deltas and settlements at the mouth of rivers?

(See an earlier post about another depiction of a delta – this depiction made by humans.)