Balkh (/bɑːlx/; Persian/Pashto: بلخ Balkh; Bactrian: βαχλο, ẞaxlɔ) was an ancient city and centre of Buddhism, Islam, and Zoroastrianism in what is now northern Afghanistan. Today it is a small town in the province of Balkh, about 20 kilometers northwest of the provincial capital, Mazar-e Sharif, and some 74 km (46 mi) south of the Amu Darya. It was one of the major cities of Khorasan, since the latter's earliest history. Marco Polo described Balkh as a "noble and great city".