In pre-Islamic Persia, Khorasan included all of Afghanistan, Uzbekistan, and Tajikistan, and bordered China. For several centuries during medieval times, Khorasan was Iran’s cultural center par excellence. It is where the great poets such as Ferdowsi and Rumi were born; where the mathematician, astronomer, and poet Omar Khayyam practiced; where scientists such as Avicenna/Ibn Sina, Farabi, and Biruni delved into medicine, physics, and geography. Today, its connection to great poets and musicians remains strong, but it is mostly known as a city where millions of Muslims come as pilgrims to visit the shrine of Imam Reza—a descendant of Prophet Mohammad and the eighth Shiite Imam.