The human habitation of Athens began to take on organized form as far back as the Neolithic Age, around 4000-3000 BC, when settlements were established on the rock of the Acropolis (near the north slopes), in the vicinity of the Ilissus River (where the temple of Olympian Zeus now stands), and in the area later occupied by the Agora. The human presence was uninterrupted throughout the Bronze Age, and in Mycenean times (1550-1050 BC) there was an important town on the Acropolis. Excavations have shown that early in the thirteenth century BC the palace of the Mycenean king was erected on five flat spots on the Acred Rock. In the middle of the same century, the Acropolis was walled for the first time, with a structure later known as the Pelasgian Wall. At the same time, a secret water cistern was dug on the north-west side of the Acropolis, thus ensuring that the city would have a supply of water when besieged.
The prestige of Mycenean Athens can be seen in the series of myths which are associated with the activities of local heroes. The first king of the city, in the myths, was Cecrops, while the most famous hero was Thesseus, son of Aethra and Aegeus. It was Theseus who was said to have freed Athens from the cruel tribute of blood which the city was forced to pay to King Minos of Crete: every nine years, the Athenians were compelled to send seven youths and seven maidens to Crete to be devoured by the terrible monster called the Minotaur. Theseus killed the Minotaur and Became king of Athens. The unification of the settlements of Attica under the leadership of Athens (the process known as synoecismus) was attributed to Theseus.