Apart from Halikarnassos, there are many other ancient cities in the peninsula. These cities are Pedasa, Telmissos (Gürece), Termera and Aspat Castle, Musgebi (Ortakent), Old and New Myndos, Uranion, Madnasa, Sibda (Side), Syangela, Theangela respectively.

Most of them are Leleg settlements. During the reign of King of Halicarnassos, the people of six of these settlements were forced to migrate to Halikarnassos, while Old Myndos and Syangela were rebuilt in different places in the Hellenistic order. Thus, a strong and built Halikarnassos was created instead of scattered and weak urbanists.
Halicarnassus
It was developed on the site of a small city called Zephyria on the peninsula where the current castle is located. It was founded by Anthes son of Poseidon from Troezen. Aiols, Ions and Dorians who came to the southern Aegean coasts formed six cities in the region.

The growth of Halikarnassos was in the period of Carian satrap Mausolos. Knowing the possibilities brought by the port cities, Mausolos created the city, which was surrounded by city walls, according to the Hellenic traditions. Halikarnassos, who boasted that he had not seen any earthquake in the Roman Age for a long time, is the birthplace of the historian Herodotos.