The ancient city known for its ruins in Greece is Delphi. Located on the slopes of Mount Parnassus, Delphi was considered the center of the world in ancient Greek mythology, known for its Oracle of Delphi, where the priestess Pythia delivered prophecies. The site was a significant religious and cultural center, attracting pilgrims from across the Greek world to consult the oracle and participate in athletic games, the Pythian Games. Delphi's ruins, including the Temple of Apollo and the ancient theater, provide insight into Greek history, religion, and architecture, making it a UNESCO World Heritage site and a key archaeological destination.