Anadolu Kavağı is where the Bosphorus excursions ferry finishes its journey. It's a pleasant spot in which to wander and have a seafood lunch at one of the touristy places on the square in front of the ferry terminal. Perched above the village are the ruins of Anadolu Kavağı Kalesi, a medieval castle that originally had eight massive towers in its walls. First built by the Byzantines, it was restored and reinforced by the Genoese in 1350, and later by the Ottomans.
Two more fortresses built by Sultan Murat IV in the 17th century are north of here. It will take you 30 to 50 minutes to walk up to the fortress from the town. Alternatively, taxis wait near the fountain in the town square just east of the ferry dock; they charge around YTL12 for the return trip with 30 minutes waiting time. Whichever way you get there, it's worth the effort for the spectacular Black Sea views. Unfortunately, the site is strewn with litter discarded by picnickers.