Lazio is one of the 20 administrative regions of Italy. Situated in the central peninsular section of the country, it has 5,864,321 inhabitants, making it the second most populated region of Italy (after Lombardy and just ahead of Campania) – and its GDP of more than €197 billion (223 billion dollars) per year means that it has the nation's second-largest regional economy. The capital of Lazio is Rome, which is also the capital and largest city of Italy.

Lazio comprises a land area of 17,242 km2 (6,657 sq mi) and it has borders with Tuscany, Umbria, and Marche to the north, Abruzzo and Molise to the east, Campania to the south, and the Tyrrhenian Sea to the west. The region is mainly flat, with small mountainous areas in the most eastern and southern districts.

More Info: en.wikipedia.org