Bodrum (ˈbodɾum) is a port city in Muğla Province, southwestern Turkey, at the entrance to the Gulf of Gökova. Its population was 35,795 at the 2012 census, with a total of 136,317 inhabitants residing within the district's borders. Known in ancient times as Halicarnassus, the city was once home to the Mausoleum at Halicarnassus, also known as the tomb of Mausolus, one of the Seven Wonders of the Ancient World.
The city was founded by Dorian Greeks. It later fell under Persian rule and became the capital city of the satrapy of Caria. Mausolus ruled Caria from here, and after his death in 353 BC, his wife Artemisia built a tomb, called the Mausoleum, for him. Macedonian forces laid siege to the city and captured it in 334 BC. After Alexander's death, the city passed to successive Hellenistic rulers and was briefly an independent kingdom until 129 BC, when it came under Roman rule. A series of natural disasters and repeated pirate attacks wreaked havoc on the area, and the city lost its importance by the time of the Byzantine era. The Knights Hospitaller arrived in 1402 and used the remains of the Mausoleum as a quarry to build Bodrum Castle. The castle and its town became known as Petronium, whence the modern name Bodrum. After the conquest of Rhodes by Suleiman the Magnificent in 1522, the town fell under Ottoman control as the Knights Hospitaller relocated to Europe.
By the 20th century, the city's economy was mainly based on fishing and sponge diving, but tourism has become the main industry in Bodrum since the late 20th century. The abundance of visitors has also contributed to Bodrum's retail and service industry. Milas–Bodrum Airport and Kos International Airport are the main airports that serve the city. The port has ferries to other nearby Turkish and Greek ports and islands, Kos being the most important. Most of the public transportation in the city is based on local share taxis and buses.
The modern name Bodrum derives from the town's medieval name Petronium, which has its roots in the Hospitaller Castle of St.