See the historic Blue Mosque façade and the surrounding square; interior visits are free but closed during the five daily prayers—plan around prayer times.
Former Ottoman imperial residence with courtyards, Imperial Treasury and Harem (Harem often requires separate ticket). Open ~9:00–17:00 (seasonal hours vary).
Choose a 1–2 hour Bosphorus cruise from Eminönü or Karaköy for scenic views of palaces, bridges and waterfront mansions; public ferries run frequently in the afternoon/evening.
If time allows before transfer, visit Süleymaniye for a quick exterior/grounds visit—open generally from morning until dusk; otherwise, enjoy a short walk around Sultanahmet.
Leave hotel with sufficient time for IST (approx 45–75min depending on traffic) or SAW (longer); Havaist buses and taxis are reliable options—arrive 2–3 hours before international flight.