As animals and humans travel desert trade routes, they stop at oases to stock up on water. Some oases are just wells in the desert; others support bustling towns. People almost always grow crops, bargain over goods and share news at oases.

As caravaneers plan their trips across the Sahara, they rely on the knowledge of oasis locations passed down through their families, as well as on their own experience. As Tuareg women move their herds of goats, sheep and donkeys from one of the Sahara's dry pastures to another, they make sure that they're never far from water.