The ancient city known for its ruins located in modern-day Turkey is Ephesus. Once a major trade and religious center in the ancient world, Ephesus is famed for its impressive structures, including the Temple of Artemis, one of the Seven Wonders of the Ancient World. The city was a significant hub for early Christianity, as it is believed that the Apostle Paul preached there. Today, Ephesus is an important archaeological site, attracting visitors from around the globe who come to explore its well-preserved ruins, such as the Library of Celsus and the Grand Theatre.