The history of the Etruscans can be traced relatively accurately, based on the examination of burial sites, artifacts, and writing. Etruscans culture that is identifiably and certainly Etruscan developed in Italy in earnest by 900 BC approximately with the Iron Age Villanovan culture, regarded as the oldest phase of Etruscan civilization. The latter gave way in the 7th century to an increasingly orientalizing culture that was influenced by Greek traders and Greek neighbors in Magna Graecia, the Hellenic civilization of southern Italy, evidenced by around 13,000 inscriptions in an alphabet similar to that of Euboean Greek, in the Pre-Indo-European Etruscan language. The burial tombs, some of which had been fabulously decorated, promotes the idea of an aristocratic city-state, with centralized power structures maintaining order and constructing public works, such as irrigation networks, roads, and town defenses.