Pergamon /ˈpɜrɡəmən/ or /ˈpɜrɡəmɒn/ or Pergamum /ˈpɜrɡəməm/ (Ancient Greek: τὸ Πέργαμον, to Pergamon, or ἡ Πέργαμος, hē Pergamos) was an ancient Greek city in Aeolis, currently located 26 kilometres (16 mi) from the Aegean Sea on a promontory on the north side of the river Caicus (modern-day Bakırçay).