Lazio is a region of central western Italy, more extensive than ancient Latium, which includes Rome, Viterbo, Rieti, Frosinone and Latina. Land has been reclaimed in the Campagna di Roma and the Pontine marshes. Cereals and olives are cultivated. White wines are produced using predominantly Trebbiano grapes, the higher quality wines sometimes being flavoured with Malvasia. Frascati is probably the best known. Castelli Romani, Colli Albani, Marino an Velletri are similar. Orvieto wines can be very good. Very few red wines are produced in Lazio. If eating gnocchi in Lazio they are more likely to be made with semolina rather than the potato of the north.