Deserts Starting with "O"
- Oahu Desert (Hawaii, USA): ~18 sq mi; unique sand dunes and volcanic formations on Oahu.
- Ordos Desert (Inner Mongolia, China): >100,000 sq mi; vast dunes, grasslands, rocky terrain—one of China's largest.
- Olkhon Desert (Lake Baikal, Russia): ~12 sq mi on Olkhon Island; windswept dunes with stunning lake views.