A peninsula in Southwest Asia at the junction of Africa and Asia consisting mainly of desert. The coasts of the peninsula are, on the west the Red Sea and the Gulf of Aqaba, on the southeast the Arabian Sea (part of the Indian Ocean), and on the northeast, the Gulf of Oman, the Strait of Hormuz, and the Persian Gulf. Its northern limit is defined by the Zagros collision zone, a mountainous uplift where a continental collision between the Arabian Plate and Asia is occurring. It merges with the Syrian Desert with no clear line of demarcation.