Jerusalem is the capital of Israel and its largest city in both population and area. Located in the Judean Mountains, between the Mediterranean Sea and the northern tip of the Dead Sea, modern Jerusalem has grown up outside the Old City. The city has a history that goes back to the 4th millennium BCE, making it one of the oldest cities in the world. Jerusalem has been the holiest city in Judaism and the spiritual center of the Jewish people since the 10th century BCE, contains a number of significant ancient Christian sites, and is considered the third-holiest city in Islam.