Sonoran Desert, USA

This scene is an original illustration set in Sonoran Desert, USA. It lies in the subtropics, where the climate is hot desert — evaporation far outruns rainfall.

A tall saguaro with several upright arms stands in the foreground. Behind it a steel windmill pump turns above a round stock tank, and a barbed-wire fence runs off toward flat-topped mesas on the horizon. The ground is coarse desert gravel with low scrub, and the early light rakes across it from one side.

Why does the saguaro grow in only one desert on Earth?

The saguaro is the tightest clue in the frame: it grows in exactly one desert on Earth, and nowhere else. The windmill and stock tank explain how cattle are kept where there is no surface water — you pump it. Mesas mean flat-lying sedimentary rock cut back by erosion. This is a hot desert that still freezes occasionally at night, which is why the cactus can live here and not further south.

Terpano is a free daily geography puzzle. You study one original illustration, place a pin on a borderless terrain map, and see how close you were. There is no account and no sign-up; progress stays in your own browser. It plays in 11 languages.