Raqqa, also called Rakka, al-Raqqah, and ar-Raqqah, is a city in Syria located on the northeast bank of the Euphrates River. The Hellenistic, Roman and Byzantine city and bishopric Callinicum (now a Latin Catholic titular see) was the capital of the Abbasid Caliphate between 796 and 809, under the reign of Caliph Harun al-Rashid. With a population of 220,488 based on the 2004 official census, Raqqa was the sixth largest city in Syria.