Are All Deserts Surrounded by Mountains? No—Many Are Open Basins

No. While some deserts lie in mountain-ringed basins (e.g., Great Basin Desert, USA; Turpan Depression, China), many are not:

• Sahara Desert (Africa): Vast, largely flat, bordered by Atlantic, Mediterranean, Sahel, Red Sea—not mountains.
• Arabian Desert: Broad peninsula plateau, coastal plains, no encircling ranges.
• Kalahari Desert (Southern Africa): Sandy basin, gentle slopes, no mountain walls.
• Australian Deserts (Great Victoria, Gibson, Simpson): Interior lowlands, distant ranges.
• Antarctic Desert: Continental ice sheet, coastal mountains only at edges.

Deserts form primarily from aridity causes (subtropical highs, rain shadows, cold currents, continentality), not topography. Mountains can create rain-shadow deserts (e.g., Atacama, Death Valley), but most deserts are not mountain-enclosed.