The Air Mountains are located in northern Niger and extend over 84,000 square kilometers within the Sahara Desert. Geologically, the area is notable for its remarkable ring dikes that enclose circular granite massifs. These in turn contain, and are surrounded by, young volcanic features, including cinder cones and lava flows. Two of the massifs are shown here: the oval one includes Mont Idoukal-n-Taghes, Niger's highest point. The montage is made up of images acquired November 5, 2017, covers an area of 45 kilometers north-south, and is located near 18 degrees north, 8.5 degrees east.
https://photojournal.jpl.nasa.gov/catalog/PIA22795