Was it only yesterday I was on holiday in Cahors in south-west France's Lot Valley? So it seems, but it was actually 10 years ago that I took myself there with a case of Châteauneuf-du-Pape just to be on the safe side. The local plonk might be OK for washing down everyday fare, but what if my friends and I fancied something decent to drink? Earlier this summer, I returned to the scene of my criminal lack of confidence to attend something rather grandiosely called the Journées Internationales du Malbec. It was three convivial days of discussion, tasting, wining and dining and I could scarcely believe the progress made by Cahors in the space of a decade.

You could be forgiven for not taking this progress on board as you gaze at the Lot River which loops like a lazy python in a series of horseshoe bends on its way to the Atlantic. With its medieval bridges, cobbled streets and imposing stone châteaux sitting proudly on the high limestone banks overlooking the river, today's Cahors, once an early centre of banking, is one of south-west France's most unspoilt ancient towns.

As a way of fast-tracking its progress, Cahors has cunningly teamed up with Argentina. At first sight that may seem strange but it was to Argentina that the malbec grape, the principal constituent of Cahors, was taken way back in the 19th century, along with a host of Bordeaux vines. Since that time, Argentina, with its sun-drenched upland vineyards, has turned malbec into a resounding international success.

Despite the silver-plated gift of association, the malbec of Cahors is a rather different animal. Where Argentinian malbec's struggle lies in containing its propensity to put on puppy fat and power, Cahors' challenge is how best to avoid leanness and astringency from the wetter, cooler conditions of the Lot Valley and its clay and limestone terraces.

When the sun shines on Cahors though, as it did in 2005, and to an extent in 2001, 2003 and 2007, the Lot Valley's marginal climate is a bonus, producing wines of generous proportions and flavours in the dark cherry and damson plum mould, yet still with a savoury bite and the ability to age without losing fruit.

Because the perception lags behind the reality, Cahors is often still regarded as a wine that needs an aeon or two to soften; sometimes it does. But the good people of Cahors are now paying much more attention to the detail of what goes on in the vineyard, harvesting the grapes riper and bringing improved winemaking techniques to the wines to reduce the rustic element. Among the best are Château du Cèdre (Les Caves de Pyrene: 01483 554750 and Great Western Wines: 01225 322800), Cosse Maisonneuve (Genesis: 020-7963 9068), Lamartine (Imperial Wines: 01986 892911), La Bérangeraie (The Vine Trail: 0117-921 1770), Domaine de Gaudou (Majestic), Lagrezette (Laithwaites: 0870 444 8383), Château Pineraie (D Byrne: 01200 423152) and Clos Triguedina (Waitrose).

From the latter, the 2004 Clos Triguedina, The Black Wine, £25, Waitrose, is a rich, blackberry jam malbec with vanilla undertones, while its younger sibling, the 2006 Le Malbec du Clos, £6.99, Waitrose, reduced to £5.59, from Wednesday, offers a mouthful of succulent mulberry fruitiness and a juicy, summery nip of acidity. The 2005 Château Lagrézette Cru D'Exception, £14.99, Laithwaites, is a modern take on Cahors with its smoky, oak aromas and rich, sour-cherry and damson fruitiness, while Chateau du Cèdre's fine 2005 Prestige Cahors, around £12.99, Les Caves de Pyrene, Great Western Wine, contains berry-fruit and vanilla-tones in abundance.

Thanks to wines such as these, I shan't be needing the Châteauneuf-du-Pape on my next visit to the enchanted valley.