Surely the most thrilling discovery in the world of wine shops is the unexpected treasure trove. These tend to be long-established independent shops in relatively obscure locations. That combination results in the perfect conditions to make a treasure trove: not enough local wine nerd customers yet low enough overheads to stay in business, resulting in a steady build-up of old vintages that don't sell, gathering dust until they are discovered by the likes of us at prices that seem too good to be true.

It's a bit like the scene in High Fidelity in which Rob gets the chance to buy invaluable old records at a bargain price. The movie version is slightly different, and was cut from the final film, but gives you the idea.

Occasionally I've come across bargains in unsuspecting off-licences and corner shops - old vintages of Guigal Crozes-Hermitage for £10, Pol Roger NV champagne with bottle age - but these tend to be one-offs. The true treasure trove is a whole shop-full of goodies, lovingly hoarded by the owner and just waiting to be discovered.

The gamble is that provenance of such bottles is far from guaranteed. Most of these bottles live in non-air-conditioned stores for years on end - but some wine can be surprisingly resilient, in my experience. And besides, the prices are often low enough to warrant the risk. Here are three examples of wine treasure troves that I've happened on, purely by chance.

There's very little information about them elsewhere online - this is another factor that keeps them undiscovered. 

The Walled Garden, Uckfield

This is the ultimate treasure trove. I discovered it by chance last weekend and was absolutely amazed. It's in the grounds of a National Trust property called Sheffield Park, which is also well worth a visit. As you drive up the road, there's a sign pointing left that says Vineyard Nursery Brewery. 

The wine shop is in a small tin-roofed shed amid a sprawling selection of plants and junkyard scrap. You can see from this photo that it is stuffed full of wine of all shapes and sizes. In one corner is a rack of sweet Riesling in half-bottles, stretching back to the 1970s. I saw a case of mid-90s dry white Bordeaux for around £15 per bottle. There are old vintages of new world wines too - O Fournier reds from 1998, d'Arenberg Ironstone Pressings from 1994, Sauternes from the 1980s. Many of the bottles are evidently long-standing residents, caked in dust and grime.

But there are new wines too - a good selection of classics from Chablis, Sancerre, Champagne and so on - some familiar names (but no big brands) and several producers they import themselves.

Between £10 and £30, there was a huge choice of wonderfully random wines, and you could quite easily create a varied cellar from scratch by buying only from them. The catch is that they only accept cash and cheque, so I couldn't buy a single thing!

Incidentally, there is a vineyard there too - just five or six rows of straggly-looking vines, in keeping with the chaotic nature of the place. Apparently, they produce a small amount of sparkling wine - though I couldn't actually see any of this on sale.

Eagle's Wines, Battersea

This is quite a rarity - a London wine shop that seems to be mostly undiscovered. It doesn't look much from the outside, nestled between a sandwich bar and a laundrette, and with old wooden signage above the door - this isn't the moneyed sort of neighbourhood in which independent merchants usually thrive.

Most of the shop range is pretty standard - that's not a criticism, it's just the same sort of wine (and beer, and snacks) you can find quite easily elsewhere. But their Australian selection is particularly good, including some old vintages of reds that are at peak maturity. I've bought some Wolf Blass from the late 1990s from Eagle's for under £20, and it was in very good nick. They also have an early vintage of Luke Lambert's Syrah as well - you can even see it on the shelf using this Google Maps 3D image!

Blas ar Fwyd

This shop in Llanwrst in north Wales is a hidden gem despite it having a very modern website, from which you can even buy online. What this doesn't reveal is that the store itself is full of strange bin ends - I picked up a 1998 Trinity Hill Syrah for £15, a 2008 German Kerner for £8, and a Cave de Tain 2008 Syrah from the Rhodaniennes - all of which were really interesting. They also have a decent selection of red bordeaux and some particularly good buys in the port section too.

Happy hunting!