Libyssa or Libysa (Λίβισσα), was a town on the north coast of the Sinus Astacenus in ancient Bithynia, on the road from Nicaea to Chalcedon. It was celebrated in antiquity as the place containing the tomb of the Carthaginian general Hannibal. In Pliny the Elder's time the town no longer existed, but the spot was noticed only because of the tumulus of Hannibal.