Bodrum is a port city in Muğla Province, in the southwestern Aegean Region of Turkey. It is located on the southern coast of Bodrum Peninsula, at a point that checks the entry into the Gulf of Gökova. The city was called Halicarnassus of Caria in ancient times and was famous for housing the Mausoleum of Mausolus, one of the Seven Wonders of the Ancient World. Bodrum Castle, built by the Crusaders in the 15th century, overlooks the harbour and the marina. The castle grounds include a Museum of Underwater Archeology and hosts several cultural festivals throughout the year. The city had a population of 118,237 in 2009.