Despite the fact that in 2011 Italy will celebrate the 150th anniversary of its political unification, geographical disparities stand out as a prominent characteristic of the country. The paper estimates the trend of the cost-of-living differentials across regions in the half-century after the Second World War. We find that the North-South gap has steadily increased, from 10 percent in 1951 to almost 20 percent in recent years. The divergence in prices highlights the delay, possibly the failure, of Italy’s economic integration. Its cost, in terms of both foregone economic growth and distributive equity, is borne by the entire Italian society.