A trip down the glistening River Douro, from the Spanish border and past the vineyards of Portugal's great red Barca Velha towards Oporto, will rapidly acquaint you with the ports and table wines of one of Europe's most picturesque wine regions.

You can even stop at the café where John and Norma Major spent a summer with the Symington family of Dow and Warre vintage port fame, sipping, er, gin and tonic. With its long tradition of English family companies, the wild and rugged Douro Valley upriver from Oporto is as English an outpost as Ooty is to India. Drawing from the olive- and cypress-lined vineyards located on drystone terraces along the valley's dramatically contoured hills, this traditional region, demarcated by the Marquis de Pombal in 1756, is starting to turn high-quality port grapes into some of Portugal's most exciting dry reds.

At Vila Nova de Gaia, across the Douro from Oporto, sit the port lodges with their names in lights like a mini-Hollywood. Oporto itself bustles with a maze of cafés, bars and restaurants. At the Bull & Bear, an innovative modern restaurant, the mouthwatering "black" pork, like the region's more traditional veal on the spit and its rich tripe and bean stew, goes superbly with the Douro's best reds from the likes of Quinta do Crasto (see below), 1999 Quinta do Vallado Douro Riserva (Bibendum, 020-7449 4120, £17.99) and Quinta la Rosa's well-crafted 2002 Douro Tinto (Booths, £8.99).

Portugal may be better known for its reds, but if you're on holiday here, you may be surprised to find that its refreshing dry whites are varied and delicious. Surrounding Oporto to north, east and south, Vinho Verde is a lush, verdant region whose mild summer climate is the ideal incubator for the refreshingly effervescent dry white wine of vinho verde itself. Made mostly from alvarinho, loureiro and trajadura, it makes for a mouthwateringly tangy summer quaffer that goes brilliantly with shellfish at Oporto's Boa Nova restaurant, or Atlantic bream baked in a salt crust at Porto da Sta Maria at Cascais.

The hilly Beiras region between Lisbon and Oporto, with its villages of granite houses and cobbled streets, comprises the classic regions of Bairrada and Dão. I never truly appreciated bairrada's beeswaxy, damsony baga grape until I tried it with suckling pig at Aguada de Cima, where José Vidal, whose father once cooked for the Queen, wood-oven roasts the leitão to achieve crunchy crackling and melting tenderness: made for bairrada from the brilliant Luis Pato (Laymont & Shaw, Cornwall, 01872 270545), or medium-bodied dão like 2000 Dão Reserva, Sogrape, Quinta dos Carvailhas, (Majestic, £7.99, 0845 605 6767) and the gluggy 2003 Vinha Palestra Tinto, Dão Sul (Jeroboams, £6.40, www.jeroboams.co.uk).

South of Lisbon and the vast Ribatejo (from here, try the plummy 2003 Quinta Lagoalva de Cima, £12.65, Jeroboams), the hot and dusty Alentejo's groves of silvery olive and brown cork oak shelter pigs, sheep and cows from the baking midday sun. João Portugal Ramos's ripe, blackberryish 2003 Trincadeira (Waitrose, £5.59) and juicy, raspberryish Cortes de Cima 2003 Chaminé (Majestic, £6.99) are representative of the kind of gutsy southern red that goes so well with the local lamb and game, seasoned with the region's fresh coriander, wild oregano and pennyroyal, not to mention its acorn-fed pork. And if you happen to be in the Algarve this summer, you may get a chance to try the new vintage of Sir Cliff's Vida Nova Rosé ( www.winesvidanova.com). All together now: "We're all going on a summer holiday".