Isfahan (Persian: اصفهان‎ Esfahān), historically also rendered in English as Ispahan, Sepahan or Hispahan, is the capital of Isfahan Province in Iran, located about 340 km south of Tehran. It has a population of 1,583,609 and is Iran's third largest city after Tehran and Mashhad. The Isfahan metropolitan area had a population of 3,430,353 in the 2006 Census, the second most populous metropolitan area in Iran after Tehran.

The cities of Zarrinshahr, Fooladshahr and Najafabad, Se-deh , Shahin-shahr, Mobarakeh, Falavarjan and chiarmahin all constitute the metropolitan city of Isfahan.

Isfahan is located on the main north-south and east-west routes crossing Iran, and was once one of the largest cities in the world. It flourished from 1050 to 1722, particularly in the 16th century under the Safavid dynasty, when it became the capital of Persia for the second time in its history. Even today, the city retains much of its past glory. It is famous for its Islamic architecture, with many beautiful boulevards, covered bridges, palaces, mosques, and minarets. This led to the Persian proverb "'Esfahān nesf-e jahān ast" (Isfahan is half of the world).