Bodrum Castle, also called the Castle of St. Peter, has stood over the harbor for more than 600 years. The Knights of Rhodes built it in the early 1400s as their base for controlling the eastern Mediterranean, reusing stones from the Mausoleum of Halicarnassus, one of the Seven Wonders of the Ancient World. Today the castle houses the Museum of Underwater Archaeology, whose collection of shipwreck finds from Turkish waters is the most important in the world. Exhibits include the Uluburun wreck, a 3,400-year-old vessel that is the oldest known seagoing ship, and the Glass Wreck Hall, which shows an 11th-century Byzantine ship as it lay on the seabed. The fortress itself rewards a slow visit: stone corridors, towers to climb, and the chambers where the knights lived.

Bodrum has about 2,400 years of recorded history. The Knights of St. John built the castle partly with stones taken from the Mausoleum of Halicarnassus, and Ottoman rule followed. Much of that construction still stands and is open to visitors.

Visitors interested in ancient and medieval sites will want a few hours here. The Greek theater and the castle both photograph best in the late afternoon.

First-time visitors and solo travelers both manage easily here. The area is walkable, and staff at most sites are used to tourists.

The Ancient Theater is a short walk uphill and still has strong natural acoustics. Bar Street starts just east of the castle, and the marina and bazaar are both within walking distance.

Nearby bazaars sell Turkish crafts and souvenirs. Tea houses in the side streets are a good place to rest between sights.