Contour Survey

Date 2004

Event ID 606715

Category Recording

Type Contour Survey

Permalink http://canmore.org.uk/event/606715

NX 2717 6482 Loch Heron, crannogs I and II (NX26SE 2). A contour survey was carried out of both crannogs in Loch Heron. Loch Heron I is the island visible in the centre of the loch and consists of large sub-angular to rounded boulders, averaging c 0.5m in diameter, and is covered in a thick layer of lacustrine organic silts. The mound is relatively large, measuring 51m NW-SE by 26m. The height from base to top is 2.2m.

Visibility in Loch Heron is poor, at less than 0.5m, but diving inspection confirmed that the island is constructed using massive timbers, both piles and horizontals. The species of these structural timbers could not be determined since they were for the most part detected by feeling beneath the silt, and visibility was quickly reduced to zero by this action. In several places, however, timbers in excess of 40cm in diameter were noted, protruding from the basal levels of the mound. The poor visibility made this difficult to determine, but it seems probable that Loch Heron I utilises a naturally raised spar of loch bed. This raised area appears to curve from NW to SE, and Loch Heron II is located at the SE end of this spar. The loch bed between the two sites is raised, and occasional stones and boulders were noted between the two sites, but no evidence of a stone or timber causeway was detected.

Loch Heron II lies 48m to the SE of crannog I, also lying along the axis of the raised loch bed spar. It is totally submerged, though a fallen tree which has washed onto the surface of the site marks its position above the water. The mound consists of stones of average diameter c 30cm, with many timbers protruding from the sides and top of the site. Several of these timbers were soft and rotten, probably indicative of the periodic exposure of the site above water. Again, the site was covered by thick silts, and inspection below the water level was difficult. This site is also reasonably large, at 44m NW-SE by 26m. The mound is less pronounced and has shallower sides than crannog I, however, and measures 1.5m from base to top.

A sample of a vertical pile from each site was taken for radiocarbon dating.

Sponsors: Dumfriesshire & Galloway Natural History and Antiquarian Society, University of Nottingham.

M G Cavers 2004