Ras al-Khaimah (räs äl-khĪˈmä) [key], sheikhdom (1995 pop. 144,430), c.650 sq mi (1,680 sq km), United Arab Emirates, SE Arabia, on the Persian Gulf; the northernmost of the seven sheikdoms in the federation. The economy is dependent on oil, first produced in 1969; coal is mined and ceramics manufactured. Among the sheikdom's biggest attractions are its many ancient sites (human habitation dates back to the 3d cent. B.C.) and its national museum. Previously affiliated with Sharjah, Ras al-Khaimah became a separate sheikhdom under British protection in 1921. After some hesitation, the sheikhdom joined the United Arab Emirates in 1972.