The Istanbul Archaeological Museum, located in what was once the outer gardens of Topkapı Palace, is the premiere destination in the country for prized artifacts of ancient civilization. Made up of three separate museums that highlight different collections (the main Archaeological Musem, the Museum of the Ancient Orient, and the Museum of Islamic Art), it'll be about $7 USD to view artifacts that range from ancient Greek statues to ancient Roman obelisks to remains of Lycia, Mesopotamia, Arabia, and other ancient civilizations. Yeah, there's a lot of old stuff. Highlights include Alexander the Great's sarcophagus, the oldest remaining peace treaty on Earth (Kadesh- 1258 BC), and a whole exhibit dedicated to fallen Troy. With over a million pieces on site, the Istanbul Archaeological Museum offers a great few hours in antiquity between the innumerable other forays available in the old city of Sultanahmet. Check out the official site for further details.