The exquisite 15th-century Blue Mosque is in the town of Mazār-e Sharīf, which lies near Afghanistan's border with Uzbekistan. Distinguished by its cobalt-blue and turquoise minarets and domes, the mosque is revered by Muslims as the tomb of Ali, son-in-law of Mohammed, the prophet and founder of Islam. Pilgrims have traveled to this mosque since it was first built.