The castle's origins date back to the knights of St. John.
This group of expatriates began in the 11th century with a church and hospital
in Jerusalem. Although belonging to he Catholic religion care was denied to
no-one. When the knights arrived they instructed their builders to remove all
usable materials from the tomb of King Mausolos as the castle construction began
in the 1400's.
The knights refered to the town as Mesy not knowing that they where in the
ancient Halicarnassus. The fortress became known as the Castle of St. Peter, the
Liberator, it served as the sole place of refugee for all Christians on the West
Coast of Asia during the time of the crusades. For over a century the castle
served as a stronghold in the knights community. Under Turkish care the castle
has undergone several uses including being a military base, a prison and a
public bath.