Lazio

Lazio is four landscapes converging on one city. North of Rome, the Tuscia is volcanic country, with crater lakes at Bolsena, Vico and Bracciano and a kitchen of freshwater fish, pulses and olive oil. East are the Apennines, shepherd country, linked by droving routes to Abruzzo. South is the Agro Pontino, marshland drained in the 1930s and now farmed for buffalo milk, vegetables and kiwi fruit. In the middle sits Rome, which for two thousand years has pulled raw materials in from all three directions.

Roman cooking has three traceable roots. The Testaccio slaughterhouse, opened in 1890, paid part of its workers' wages in the quinto quarto (the fifth quarter, meaning tail, tripe, intestines, offal), which is where oxtail stew and Roman tripe come from. The Jewish ghetto contributed the frying tradition: whole artichokes opened out like flowers and fried twice, courgette blossoms, salt cod fillets. And seasonal sheep migration from Abruzzo brought pecorino romano, guanciale and milk-fed lamb, the pantry everything else rests on.

The four famous pastas are really one formula with three variables. Gricia is the base: guanciale, pecorino, pepper. Add tomato and it becomes amatriciana; add egg and it becomes carbonara; take out the pork and you have cacio e pepe. None is as old as it sounds (carbonara appears in cookbooks only in the 1950s) but the logic is a shepherd's larder, where salted cheese and pork fat were the things that kept.

Outside the ring road the food changes every fifty kilometres. The Sabina hills north-east of Rome make one of Europe's first protected olive oils, from groves that include thousand-year-old trees; Amatrice, in the same province, gave the amatriciana its name. Ciociaria, to the south, has raw-milk Picinisco sheep's cheese, Atina cannellini beans and Cesanese del Piglio, the region's one serious red. The Castelli Romani hills above Rome supply porchetta from Ariccia and Frascati wine, drunk in plain rooms called fraschette. And the Roman artichoke (round, thornless, sold in February to April) comes from the coastal fields at Ladispoli and Cerveteri.