At the very top of the country we find Castle Varrich overlooking the Kyle of Tongue,

The castle walls are generally 1.4 metres (5 ft) thick, or thicker, and have been built from roughly squared blocks of metamorphosed sandstone rock of varying thickness, laid in rough courses of random depth. The stones seem to have been laid without the use of mortar, and have suffered little from weathering, considering that the building may be 1000 years old, (wikipedia)

HWW ! large view recommended!