A woman that worked at the hotel we stayed at last night insisted we stop by Céide Fields as we went through, and that was good advice. You’ve likely never heard of it, but this is the world’s most extensive Stone Age monument. It’s a system of fields, the remnants of dwelling areas and the megalithic tombs sprawling out over hundreds hectares, and it dates back almost 6,000 years.

This is the oldest such example we have in the archeological record, and it’s worth stopping to consider. The people were managing fields and livestock, six millennia ago. Since we were just learning, at our last stop, about the preservative nature of the bogs, it’s reasonable to think that there were other such places like this … indeed, the thinking is that the techniques used here came with the people as they moved from West Asia through Europe. Here’s an artist’s conception of what it might have looked like.

And here’s a bit of the wall ruins. That little white post is an important marker. The white posts trace the outline of where the archeologists have found the walls.

You can see more of those markers here. We’re walking on this path, but we’re walking right next to one of the walls. They’ve found more than 62 miles of walls, and some of their buildings and tombs. The walls managed cattle, and they were a little more than 3-feet tall. (Even back then, cattle couldn’t jump.) Over the years it got colder and wetter here, and the speculation is that this is what led to the abandonment of the land.

The work is hardly done. There’s a lot of land here to explore, and it’s a manual operation, full of physically probing the earth for the well-preserved evidence of the people that worked on the land. You walk through the visitor’s center, so that you may pay, and they direct you outside into the fields, so that you may see a glimpse of the work. You learn that the composition of the ground means it is a manual and physical exploration.

It didn’t always look like this.

The settlers found woodlands, birch and pine. What they left had been understood in some small way by the locals for at least a century, but it wasn’t until the 1970s that the significance of the place came together for researchers. And while there’s a lot they don’t know, they are still piecing it together.

There’s a great satellite photo that has a graphic showing the rediscovered walls. You can see how the straight lines of the wall remnants continue on beyond the drawn lines. Sometimes they follow the contours of the earth, and sometimes they make the contours. While the weather changed, people would have either moved back or moved off. And if there’s one thing we know its that people will use the resources around them, so some of those old stone fences stayed fences, or the stones themselves might have been repurposed. And it’s all quite interesting.

I asked them if they’d tried lidar, and apparently just last year they’d had some side scanning done. The guy, who really wanted to go home and not answer my silly questions, said they were waiting for more on the results. I should probably set a news alert for that.

But would you like to see the most interesting thing?

This is a tree that fell more than 4,300 years ago. It’s a pine tree. A schoolteacher dug it up just four miles from here, one of the largest bog pines found in the area.

That schoolteacher, Patrick Caulfield, started putting two-and-two together about all of the stones he kept running across while he was cutting turf, for heat. He’d noticed the stones were piled in lines and reasoned that that wasn’t natural. Maybe they were put there by people. Maybe the rocks were there before the bog started to take hold.

His son, Seamas Caulfield, studied archeology, and it was Seamas who started adding some context. There’s some debate about whether all of this is from the stone or bronze age, and so the work goes on, but we are looking at a 4,300 tree. And it’s beautiful.

I wonder what you could make with lumber that is thousands of years old. And now I’ll spend the rest of our trip wondering what I’m walking over in the well-preserved earth.

Sometimes, in thin places, the informed guesses of archeology don’t feel sufficient to tell the story of a place. Imagine, then, how inadequate the rest of us must feel trying to understand or explain it.

We saw another landmark that people use from the sea. It’s a point on the tip of a peninsula. And we didn’t see the whole of it, but we got close to Ceann Iorrais, or Erris Head.

The scenic viewpoint of Erris Head is said to give you views of the ocean and rocky cliffs. You have to go across a number of fields. Today, they were very muddy fields. It’s also a conservation area. Seabirds nest on the cliffs, included gulls and falcons, Irish crows, and more. You’ll also see geese, seals and other critters depending on the season. You can sometimes sea the dolphins and porpoises at sea.

If you could walk the route — up and off to the left from these first photos — it’s about three miles, and you’d see some old naval watch posts, and the ancient stones that make up some of the most exposed coast in this part of the world. The cliffs, made of quartzite, gneiss, and slates aren’t especially tall, rising just 295 feet above the sea.

Some of them are thought to be the oldest rocks in Ireland, dating back 1.8 billion years.

When the first people came to this area, it was native woodland, and had been since (relatively) shortly after the last Ice Age.

During the Neolithic period, about 6,000 years ago, the first people living in Ireland began to cut down the forests to clear land for growing crops and grazing livestock. Just below a thin layer of soil were those old rocks, and so erosion took its toil. When the crops began to fail, and this probably just took a few years, the Neolithic people had to clear the native woodlands further and further inland for their crops.

In the 1930s R. L. Praeger, a naturalist, described this as “the wildest, loneliest stretch of country to be found in all of Ireland … ”

Ocean and wind energy are the future around here. Folklore is a part of the past and the present. There’s one tale about a jealous stepmother who doomed her kids to spend 900 years as swans on the lakes and waters around the island. Another good one is about the mounds of the earth near a nearby village. They haven’t been explored, but are apparently not naturally occurring. The story goes that you had to pay a toll to come onto the peninsula or you were never seen again. I’m not sure if you can call that a case of highwaymen, since roads are a relatively new development around here, the first having come into service less than two centuries ago.

We made a quick stop to start the day at a place that’s been historically relevant in more than one way and in more than one time. Blacksod Lighthouse has been in operation since 1866. It remains an active lighthouse. It is waymark for local fisherman, has been a post office for the community, and still serves as a fueling stop for the locals and also emergency operations.

Just out of view here is a small collection of signs memorializing the vessels and people that left from these shores during tough times. This was the place where struggling, starving people set out for Great Britain and Canada and the United States. You can just come to the little beach here and do a little genealogical work if you are of Irish descent.

The lighthouse hasn’t opened for seasonal tours just yet, and it’s a quiet spot in the midmorning. Just two other people were there, having a picnic on the stone wall overlooking the water. Behind the building is the rocky beach. Just off the right of the frame is where you’ll find the garden with all of the immigrant vessels.

Then, in 1944, the people working here played their role in saving the free world.

Blacksod, as a weather station, measured atmospheric conditions and made regular reports to Britain and the US. There were no satellites or computer models, of course, there was only first-person observation, extrapolation, and educated guesswork. A young woman, Maureen Sweeney, was a part of that effort. She worked there in the mail office and also made hourly weather observations from this key spot, one of the first stations on the western coast. On her 21st birthday she saw the coming storm that threatened the armada assembled in the English Channel for northern France. Men were sick in the boats, nervously waiting to go ashore or jump into France or ferry others here and there. It was the world’s largest military operation and it came down to secrecy, timing, the tides and the moon, and the weather. What Sweeney saw helped generate the forecasts that convinced Gen. Dwight Eisenhower, to postpone the invasion by a day.

There’s a movie due out this summer about the weather, full of wonderful actors all delightfully miscast. But the star will be the history, and that weather. Some of it was recorded and reported at this spot, at Blacksod.

Maureen Sweeney stayed on there, running the mail, until she retired in her 80s. She died at 100, just a few years ago. Working here is a family business. Her son runs the lighthouse these days.