Clearance Cairns- a mystery solved.

While we were wandering about, photographing some abandoned farms in Cwm Dulyn, we encountered a couple of cairns whose shape and construction seemed difficult to explain. They were very carefully built showing considerable skill. They were very old, too- judging by the lichen growth on them. Strangest of all, they were slap bang next to an enclosure wall, which also passed very closely by a row of three standing stones.

A swarm of cairns in Cwm Pennant. Like the ones in Cwm Dulyn, they are placed on top of a much larger, immoveable rock.

We pondered this for a while, then I remembered seeing something similar in Cwm Pennant- again very old, on rough moorland that bore the signs of ancient cultivation. I had read a blog that suggested these were ritual or funerary markers made by bronze age peoples, but somehow, that didn't seem right. I asked around and one or two people suggested that they could be field clearance cairns. This doesn't necessarily mean that they are recent, as clearance cairns can date back to the neolithic farmers. But it did seem a lot more plausible.
Of course, once you have seen something, and have an idea about it, you start to see that thing everywhere, and so it was on our next few explores where we were again roaming over moorland looking for old settlements

Two cairns in a field at Hafod y Gors wen- a consumption wall is on the right...leaving little doubt that these are clearance cairns.

There are a few guidelines for recognising clearance cairns. The old ones are usually on moorland;  they will be associated with ancient settlements and often are completely covered over with moss or grass. Often there will be evidence of long-abandoned cultivation such as ridge and furrow marks and ancient walls.  They will also  be composed of stones that can be carried easily by hand. More modern clearance cairns are made of larger stones, moved by machinery.

A very old cairn at the end of an ancient wall line above Cors y Gedol. There were ridge and furrow marks in the field which was obviously mediaeval- or older.

Sometimes, the cairns are grouped together in a circle (we found one above Dyffryn Ardudwy that was obviously ancient) and it has been suggested that there is some ritual significance in this. But generally, bronze age and earlier cairns are so common (once you start to see them) that the claim seems hard to justify.

A consumption wall arranged as a sheepfold (gorlan). Hafod y Gors.

The cairns are not to be confused with "Consumption Walls" which are sometimes of a similar age, but are thickly constructed walls, sometimes as much as ten feet in width, constructed simply to clear the surrounding fields.
The obvious reason that the stones were cleared is that the early ploughs found it hard to work in stony ground, especially since at first, the blades/mouldboards were made of wood. It would be very advantageous to get rid of as many stones as possible. Later, the stones would make a handy source of  walling, or could be used as markers and boundaries.
One thing is for sure, whatever the date of some of the cairns we found, many were built with some skill. They are not just random piles of stones.

A view of one of the cairn group in Cwm Pennant.

One of several cairns at Hafod y Gors

Showing the skilful nature of the construction.

More Consumption piles, this time opportunistically, on a ledge in a rock face! Hafod y Carreg.

Older cairns on solid blocks at Pen y Gaer. Some have been robbed to make the wall, others are completely grass-grown.