Pergamon or Pergamum (/ˈpɜːrɡəmən/ or /ˈpɜːrɡəmɒn/; Ancient Greek: Πέργαμον), also referred to by its modern Greek form Pergamos (Πέργαμος), was a rich and powerful ancient Greek city in Aeolis. It is located 26 kilometres (16 mi) from the modern coastline of the Aegean Sea on a promontory on the north side of the river Caicus (modern-day Bakırçay) and northwest of the modern city of Bergama, Turkey.
During the Hellenistic period, it became the capital of the Kingdom of Pergamon in 281–133 BC under the Attalid dynasty, who transformed it into one of the major cultural centres of the Greek world. The remains of many of its monuments are still visible today, most notably the masterpiece of the Pergamon Altar. Pergamon was the northernmost of the seven churches of Asia cited in the New Testament Book of Revelation.