The first prehistoric site of the day, the earthwork is prominent enough to find it even in the gloom (well, principally because the forestry path comes out right next to it). The views from here, when there are some, would be obscured to the north by the trees. It may be possible to see the Black Mixen summit from here. Who knows? A round barrow is shown on the map a little way to the northeast, but today isn't the day to investigate.

Instead, I squelch southeast, heading towards Black Mixen (OE: Black Dunghill), the second summit of the day. At least this section follows a clearly defined track. On a normal day, the enormous radio mast that tops the summit of the mountain would provide a foolproof landmark, but I can't even see that today. Like the summit of Great Rhos, this a flat, boggy area, characterised by spongy peat and tussocky heather. The radio mast finally emerges, and close by I can just make out the trig pillar. This one stands on a confirmed round barrow, although in truth it looks almost identical to the mound that the Great Rhos trig rests on. The top of the barrow is flattened, presumably by the usual digging and erosion rather than just from the incorporation of the trig pillar. Not a spot to linger on a day like this, with wet feet and a long way to go still. I head off and the barrow vanishes behind, real or imagined I cannot truthfully say.

To my south, barrows appear on the top the Whimble and the western summit of Bache Hill. By now I'm too tired to leave my main route and visit them, so they'll have to wait for another day. But the summit of Bache Hill itself now looms ahead, just a matter of climbing the grassy field and I'm there. The barrow here is magnificent. Much larger than the Black Mixen barrow, although similarly topped with a trig pillar, this is as fine a specimen of a round barrow as you could hope to find, especially on top of a Welsh mountain.

I collapse at the barrow, wring my socks again, have some lunch. As I sit, the surrounding gloom begins to lift properly, revealing an astonishing view to the south. First of all, patchwork fields emerge across the farmland below, finally acknowledging the elevation attained up here. Then, much further south, a black ridge of hills becomes visible: the Black Mountains escarpment. As the sharp profile of Mynydd Troed clears, I have an warming sense of place, with another piece slotted home into my Welsh jigsaw. I must come here again, when the views are clearer and my feet are drier. But in some ways the all-covering mists, giving way to a tease and a slow reveal, has heightened the satisfaction of making it up here.

There is a further barrow to the east of the main one, less impressive in itself but perfectly situated on the edge of the summit ridge overlooking the farmland below.

I have been to Kinnerton once before and visited the round stone in its field, but didn't know about the second stone tucked into the verge to the north of the field gate. I only find this now thanks to Postie's pictures – it's very overgrown and nettles sting me in my efforts to clear it sufficiently to photograph.

As has been commented by others, the stone in the field mirrors the conical top of The Whimble, visible to the west from here.

Heading south along quiet lanes, the Crossfield Lane round barrow can be seen over a field gate. Although once a large barrow, over 30m across, it's now been ploughed down to little more than a rise in the field.

Arriving at Four Stones provides an emotional punch in the guts. The last visit here was with my Dad, on one of our last days out together in 1999. Coming back here is nearly overwhelming and I find myself in tears, thinking of all the things we never said and all the things we never had time to do. I will experience something similar at Mitchell's Fold the following spring, showing that the healing we think time brings isn't either as complete or as secure as it seems. These sites bring such thoughts into sharp relief.

But although Four Stones has the power to open me up, it also has the power to bring a stupid grin. The four boulders, so closely spaced as to enclose the visitor in a tight embrace, exert a strong pull on the senses. The proximity of a nearby house and occasional passing car, the recently cut hay in the field, all fade out of mind as I sit here. The views of the now-revealed Radnor mountains, that I was so recently stumbling across in the mist, add to the overall feeling that this circle is a small part of a grand landscape. And we sit in it, briefly, then we're gone and it endures, for the next visitors. Long may that continue.

I'm thinking about it all and I'm sorry and I'm not sorry - our time was made up of confused emotions and little whirlwinds and all those things we couldn't really talk about but, most of all, it was sealed in sacred moments like these and then it was gone.