Museum of Underwater Archaeology  

In 1962 the Turkish Government decided to turn the castle into a museum for the many underwater discoveries of ancient shipwrecks in the Aegean Sea. This has become the Bodrum Museum of Underwater Archaeology[3], with a vast collection of amphoras, ancient glass, bronze, clay, iron items. It is the biggest of its kind devoted to underwater archaeology. Most of its collection dates from underwater excavations after 1960.

These excavations were performed on several shipwrecks :

Finike-Gelidonya shipwreck (12th c. BC) : 1958 - 1959 ; first underwater dig in Turkey [4], showing that Near Eastern merchant ships played a much greater role in the Bronze Age than previously known.
Bodrum-Yassiada shipwreck (Byzantine, 7 th c. AD) : 1961 - 1964 ; Roman merchant vessel with 900 amphoras.
Bodrum -Yassiada shipwreck (Late Roman, 4th c. AD)
Bodrum-Yassiada shipwreck (Ottoman, 16th c. AD) (dated by a sixteenth-century 4-real silver coin from Seville (Philip II) )
Seytan Deresi shipwreck (16th c. BC)
Marmaris-Serçe harbour shipwreck (glass, 11th c. AD) : 1977; amazing collection of Islamic glassware

Marmaris-Serçe harbour shipwreck (Hellenistic, 3th BC)
Kas-Uluburun shipwreck (14th c. BC) : 1982 - 1995; 10 tons of Cypriot copper ingots; one ton of pure tin ingots; 150 glass ingots; manufactured goods; Mycenaean pottery; Egyptian seals (with a seal of queen Nefertiti) and jewelry [5]
Tektaṣ glasswreck (5th c. BC) : (1996-2001) [6]
The former chapel houses an exhibition of vases and amphoras form the Mycenaean age (14-12th c. BC) and findings from the Bronze Age (around 2500 BC). The many commercial amphoras give a historical overview of the development of amphoras and their varied uses. [7]

The Italian Tower houses in the Coin and Jewelry Hall a large collection spanning many centuries.

Another exhibition room is devoted exclusively to the tomb of a Carian princess, who died between 360 and 325 BC.

The collection of ancient glass objects is one of the four biggest ancient glass collections in the world.

Two ancient shipwrecks have been reconstructed : the Fatımi ship, detected as sunken 935 years ago, and the large Uluburun Shipwreck from the 14th century BC.

The garden inside the castle is a collection of almost every plant and tree of the Mediterranean region, some of which have a mythological significance : the myrtle was dedicated to Aphrodite; the shadow of the plane tree was sought after by kings and noblemen, as it was thought to strengthen one's health.