premise: Each of the five areas has a principal city as a focus or starting Rome for central Italy, plus Sardinia; Florence for Tuscany, with Umbria, and the Adriatic seaside resorts to the east; Venice for Veneto, the Dolomites, and Emilia's historic towns from Parma to Ravenna; Milan for Lombardy, Piedmont, and the Italian Riviera to the west; and Naples for the south and Sicily.
hypothesis: Aside from Rome, Naples is the most populated city in Italy.