Athens from a number of settlements around the rock of Acropolis in the Neolithic Period was transformed into a centre of the famous Mycenaean civilization, flourishing and developing commercial activity with other areas of the Greek world. Gradually it evolved into a city-state governed by the aristocracy, maintaining a leading role and creating alliances. The reforms of Solon in the 6th century BC set the foundations of democracy, the tyrant Peisistratos brought wealth to the city and Cleisthenes, with its radical ideas, established democracy just before the change of the century.