The twelve islands boat trip is one of Fethiye's most popular excursions — a full-day cruise on a traditional wooden gulet around the islands and coves of the bay. The standard route includes swimming stops at Tersane Island (with a ruined Ottoman shipyard), Yassıca Islands (flat rocks perfect for sunbathing), and Kızılada (Red Island). Lunch is usually included, cooked on board.
Boats depart from Fethiye harbour in the morning and return by late afternoon. The trip is widely sold by travel agencies and hotels — prices are competitive so shop around. The boats vary from large party boats with loud music to smaller, quieter vessels. If you want a peaceful day, ask specifically for a smaller boat or book a private trip. The swimming is excellent — the bay is sheltered and the water is clear.