Isfahan , which is located in the center of Iran, is a vibrant city stretching along a spectacular river with three UNESCO world heritage sites, ancient Islamic architecture friendly and hospitable locals, gorgeous bridges, and plenty of hidden locations to discover. Isfahan, the third biggest city in Iran, should be top of every traveler’s list in Iran.The history of Isfahan dates back to ancient times. During the Achaemenid Empire (648–330 BCE), Isfahan was an ethnically and religiously diverse and tolerant city. Isfahan was once one of the largest cities in the world, ranked among places like Athens or Romeand grander than London, Paris and Istanbul.Elegant bridges crossed its modest river, hundreds of domes and minarets punctuated the skyline and polo players dashed across the world's largest square. Isfahan flourished from the early 11th to the 18th century, and particularly during the Safavid dynasty in the 16th & 17th century when it became the capital of the old Persia for the second time.