Eadar a’ Chalder Heritage Trail
From Ardvreck Castle car park (1) head north-north-west along the road for a few yards until you are opposite a gated track on the right. Take care crossing the road and go through the gate and up the track.
You may want to take a diversion to the flat area between the stream and the road, where there is a massive grinding stone. This was used in a limestone mill for crushing the rock. The ground limestone was probably used elsewhere for sweetening acid soil.
The presence of this mill is an indication of the underlying geology of all the ground covered in this trail, which has made it some of the best grazing ground in Assynt and thus the heart of political and social struggle for power. The limestone was laid down as deposits, rich in marine life, in an ancient shallow sea, and these calcarious deposits make the soil slightly alkaline and good for sweet grasses. This is in stark contrast to most of the rest of the parish, where the soils are acidic, peaty and provide poor, rough grazing.
Look across the loch to Ben Garbh, where you can see clearly the two other main kinds of rock in Assynt. The lower part of the hill is rough and lumpy. This is Lewisian gneiss, some of the oldest rock in the world, made from the earth’s core up to three billion years ago, not that long, geologically speaking, after the planet itself was formed. The upper part of the hill is clearly formed of horizontal bands of a more even rock. This is Torridonian sandstone, formed from sediments in freshwater lochs around a billion years ago. The limestone under your feet is a mere half billion years old – relatively young, at least to geologists.
On this side of the loch, the geology is very complex, because it is the zone that crumpled when the Iepetus sea closed up between Assynt (which was at that time joined onto a continent that is now North America) and the European continent. This collision built the Caledonian mountains, the stumps of which are all that remain of a range that was then of Himalayan proportions but has since eroded away. The erosion here has exposed the zone of crumpling so clearly that geologists from all over the world come here to gain understanding of plate tectonics and other geological forces.
One of the effects of this smashing together of continents is that the rocks here have been broken into pieces and shunted over each other, like a pack of cards, known as an imbricate structure. We will cross some of these layers on this walk, so beware that the landscape can be a bit confusing.
Walk up the path about 200 metres from the gate. In the stream gully to the left there are some trees, and before you pass the ivy-covered tree and holly, you should turn right, off the path and head up a slope. Within 100 metres of the path you will clearly see a ruin ahead with pointed eaves still standing with a hole in one end. Walk towards this, noting the footing of a small building on the left (2). This small building is all that remains of a poor subtenant’s house and dates back at least to the mid eighteenth century. It had fallen out of use before the area was mapped in 1774 and may be much older, although subtenants were still living in similar houses into the 19th century.
The much larger ruin (3) was built in the 1770’s for Alexander MacKenzie who rented Eddrachalda Farm from the Sutherland estate and controlled the land inhabited by several other families. It is notable for the signs that remain of sophisticated masonry including recessed windows, lime mortar, corner stones that must have been worked and carried in, fireplaces and cupboards at both ends of the house and internal plaster. It would have been an impressive house of a completely different standard to those of the subtenants. would have been an impressive house of a completely different standard to those around about it.
Beyond it to the south east are several ruins that are clearly built of the local stone, with more traditional rounded corners which may have served as barns. There is also a substantial enclosed area, purpose unknown, but probably a kale yard or seasonal animal enclosure. Just to the north east of the enclosure a cluster of ruins on a higher terrace may include the remains of an earlier farmhouse – a long rectangular structure with sharply angled corners and space for livestock at one end.
Leave this settlement from the diagonally opposite corner of the enclosure from the big house, heading east-south-east uphill. On the first ridge you can look south east to the tree-lined ravine of the river, the Allt an Chalder Mor. This name means Big River of the Calder, and calder is ambiguous, possibly coming from the norse for cold water (Would the source of the water in limestone caves upstream cause this water to be notably colder than any other burns in Assynt?), or maybe from an older Gaelic term concerning domestic animals. Whatever its origin, to the north there is the Allt an Chalder Beag, the small river of the Calder, so this area’s name, Eadar a’ Chalder means ‘between the Calders’.
Facing towards the river, you are now in a small glen with a dyke running down its length. Walk down to a very ambiguous stone feature (4) between the ridge and the wall. What is this? Archaeologists are uncertain, but it seems to include animal pens and a larger oval structure. It might possibly have started out as a round house which was then converted for multiple purposes over the centuries.
On the other side of the wall and a few metres further towards the river is a smaller stone structure, believed to be the remains of a bronze age cist (5), which would once probably have had a cairn over it (most of which is presumably now in the wall).
Follow the wall down, and you will come across more buildings closer to the river, including a structure built into the dyke (6). It was mapped in 1774 and may have been a subtenant’s house. Keep up above the river as it jack-knifes, contouring south to another house or outbuilding (7) with possible small kale yard or livestock enclosure which was also mapped in 1774.
This is a beautiful stretch of river, the sound of which, in spate, is thrilling. There is a wealth of tree species in the ravine, including holly and elm, and it has been a refuge from grazing animals for thousands of years. As you carry on, above the ravine, following the river down to the loch, see if you can spot trees among the grass, as the woodland is trying to regenerate now that grazing levels are lower than they have been in the past.
Head back towards the car park, In this hinterland, you have seen some traces of the society and land uses on which the wealth of the owners of the castle and Calda House were built.