Saudi Arabia,[d] officially the Kingdom of Saudi Arabia (KSA),[e] is a country in West Asia. Located in the centre of the Middle East, it covers the bulk of the Arabian Peninsula and has a land area of about 2,150,000 km2 (830,000 sq mi), making it the fifth-largest country in Asia, the largest in the Middle East, and the twelfth-largest in the world. It is bordered by the Red Sea to the west; Jordan, Iraq, and Kuwait to the north; the Persian Gulf, Bahrain, Qatar and the United Arab Emirates to the east; Oman to the southeast; and Yemen to the south. The Gulf of Aqaba in the northwest separates Saudi Arabia from Egypt and Israel.[15][16] Saudi Arabia is the only country with a coastline along both the Red Sea and the Arabian Gulf, and most of its terrain consists of arid desert, lowland, steppe, and mountains. The capital and largest city is Riyadh; other major cities include Jeddah and the two holiest cities in Islam, Mecca and Medina. With a population of almost 32.2 million, Saudi Arabia is the fourth most populous country in the Arab world.