Ayvalık is a municipality and district located in the Balıkesir Province of Turkey. Situated on the northwestern Aegean coast, it serves as a seaside town with an area of 305 km2 and a population of 75,126 as of 2024.
The town center is connected to Cunda Island via a causeway. It is surrounded by the Ayvalık Islands archipelago, which faces the nearby Greek island of Lesbos.