Baghdad (, transliterated "Baghdād") is the capital city and largest city in Iraq. It is the second-largest city in Southwest Asia after Tehran. It is the second-largest city in the Arab world after Cairo. It has 5,772,000 people (2003). Baghdad is on the Tigris River at 33°20′N 44°26′E. The city was once the center of Dar al-Islam, Muslim civilization.