On our recent minimoon to Rome we went exploring an ancient pre-Roman Necropoli northwest of the capital at Cerveteri.
Around 600BC at the height of its influence Cisra, as it was known, had a population of c.25,000-40,000 people! It's wealth derived from the nearby iron-ore mines and its vicinity to the sea, ideal for trading.
The earliest tombs date from the Villanovan culture of the 9th century BC and was used all the way up to the 3rd century BC.