Extremely dry

A mound or ridge of sand formed by the wind

A seasonal wind that brings heavy rains in the summer, and dry air inland in the winter

A hot, dry, suffocating wind that blows during summer in the Arabian Peninsula; this term translates to "poison" in Arabic

A northwesterly wind in the Persian Gulf area which carry millions of tons of sand and silt into the Rub' al-Khali

A territory ruled by an Arab tribal leader

A branch of Islam that regards the first four successors of Muhammad as his rightful successors (85% of the Muslim population)

A branch of Islam that regards Muhammad's son-in-law Ali and the imams as his rightful successors (15% of the Muslim population)

A conservative form of Islam distinct from Sunni and Shia sects; prominent in Oman

Islamic law derived from the Koran and the teachings of Muhammad

In Islam, the yearly pilgrimage to Makkah (Mecca) that Muslims take at least once in a lifetime

Government policy as it is influenced by physical, human, and economic geography

The removal of salt from seawater or brackish groundwater to make it usable for drinking and farming

This landform runs along the coast of the Red Sea and is composed of hard, ancient rocks covered with extinct volcanoes

Part of the Arabian Desert, this is largest uninterrupted area of sand in the world; also known as the "Empty Quarter"

Green areas fed by underground water sources that are found in deserts

"City of the Prophet" or "The Enlightened City"; this holy city is the location of the prophet Muhammad's tomb

The holiest city in Islam, and the birth place of the prophet Muhammad. Millions of Muslims make a pilgrimage to this city every year

The capital of Saudi Arabia and largest city on the Arabian Peninsula. It is the center of oil refining in the region and home to the royal palace of the King