Ceide Fields isn't somewhere you'd find by accident. Perched on the cliffs above the Atlantic, it's at the furthest fringes of the west of Ireland, at the very edge of Europe.
But hidden treasures always take a little digging - and if you persevere along the coast road, past the village of Ballycastle in County Mayo, with grey stone walls on one side and the roaring sea on the other, you'll find what is one of the most significant prehistoric sites in western Europe.
Ceide Fields (pronounced like "cajun" without the n), which has been called a "slow-motion Pompeii", is a Stone Age farming settlement preserved beneath the peat bog that swamped the site about 5,000 years ago. Bad news for the original farmers who were pushed off their land by the slow spread of this great soggy blanket. But for archaeologists, once the layers of turf are peeled back, underneath lies a landscape untouched since it was abandoned.
Standing at the entrance to the Ceide Fields is a futuristic, pyramid-shaped visitors' centre. Inside is an exhibition that attempts to place the archaeological evidence in its historical context, showing the kind of homesteads that might have been standing in these fields and how climate change and deforestation combined to turn the ground into sodden bogland. And a timeline emphasises the sheer antiquity of the site - people were living and working here before the pyramids were built in Egypt.
Around 1,000 people lived on the original Ceide Fields, growing crops such as barley and wheat and keeping animals on farms divided by dry-stone walls. These rectangular plots vary between five and 17 acres. Archaeologists were also intrigued to find no defensive walls around the settlement, suggesting the community faced no great external threats.
Once you've done your homework in the exhibition halls, you can pace around the site which is where you can let your imagination work. There are pathways across the site, which is still mostly unexcavated, and guided tours explain how the settlement was divided up.
If you look at the map of how the fields were divided, you realise that the inhabitants must have been well-organised and sociable people, presumably having rules and customs that dictated how they lived and worked together. How did they decide who got the biggest fields? How did they settle disputes? Even if their technology stretched no further than a plough, their society must have been evolved enough for people to live together successfully. A thousand people can't live together without a lot of talking, politics, romance and gossip.
Apart from its claims to historical significance, Ceide Fields is also big on atmosphere. It's a wild, brooding stretch of high ground overlooking the Atlantic Ocean, and you can imagine that it wouldn't have looked much different when our Stone Age forebears were tilling the fields here. Some locals are resolutely sceptical, saying there's nothing to see - no cave paintings as in Lascaux or stone circles as in Stonehenge - just a few walls in a field of the type you'd see in any old field.
And although this is the oldest known field system in the world - and so is perhaps entitled to look a little weather-beaten - these locals have a point, because an intriguing aspect of the outlines of farms and buildings uncovered is the continuity with today's landscape. The network of small farms suggested by the Ceide Fields could be mistaken for the pattern of farming that still survives here.
The shape of the Neolithic homesteads is strikingly similar to that of the traditional cottages you can see all over the west of Ireland. And the stone walls found beneath four metres of bog are more or less the same as the walls that snake around hillsides. Which is a bit like art historians painstakingly stripping off the top layer of a painting and finding exactly the same picture beneath. This suggests that a very ancient way of life, which survived the arrival of incomers such as the Celts, has much more in common with the present than might have been expected.
This continuity was described more poetically by Seamus Heaney, who wrote:
"A landscape fossilised Its stone-wall patternings Repeated before our eyes In the stone walls of Mayo."
In fact, this is the kind of place that lends itself to poetry (and frostbite, because it's always freezing). It's windswept and dramatic, with the kind of views that tourist brochures like to pretend are typical. Plus a few old stone walls in a field.
Ceide Fields, Ballycastle, County Mayo, Republic of Ireland. Adults pound;2.50, children pound;1. Open 9.30am to 6.30pm. Tel: (00353) 964 3325. Flights from London Stansted to Knock airport on Ryanair (www.ryanair.com)