Kiz Kulesi (Leander's Tower - Maiden Tower): A 12th century stone tower erected on a rock at the entrance of the Bosphorus. This tower, which has served as a prison and a lighthouse, became the source of many legends in ancient days. It's now open to the public as a cafeteria and an elegant restaurant which hosts concerts and meetings as well. Transportation to the Tower is valid by private shuttle boats from both shores of the Bosphorus.
Galata Kulesi (Galata Tower): A 55 meter tower providing a panoramic view of the old town, Galata Tower was built by the Genoese as part of the wall surrounding their district of Galata directly opposite Byzantium (Constantinopolis). The tower now houses a restaurant.
Anadoluhisari (Anatolian Fortress): A 14th century relic of the Ottoman's first attempt to conquer Istanbul, Anatolia Fortress is located on the Asian shore at the narrowest point of the Bosphorus. Sultan Yildirim Bayezit built this fortress in 1393 on the ruins of a Byzantine temple dedicated to Zeus. It's much smaller in size when you compare with Rumelihisarı on the European side of Istanbul.
Rumelihisari (Rumeli Fortress): Sultan Mehmet the Conqueror built Rumeli Fortress in just four months directly to the opposite of the Anadoluhisari in 1452 in preparation for the final attack on Constantinople (Istanbul), which led to the downfall of the Byzantine Empire. Today, the fortress hosts many concerts and dramatic performances in its amphitheatre in summer. The fort is open to the public as a museum as well (except on Mondays).
Misir Carsisi (The Egyptian Spice Bazaar)
Built in the 17th century next to the Golden Horn, the Spice Bazaar is the second largest covered bazaar in Istanbul. Originally housing shops selling medicine and spices, the Spice Bazaar continues to fulfill its original function. This distinguished example of Ottoman architecture continues to sparkle with life even today. Open every day except Sundays and National Holidays.