Field Visit
Date June 1992
Event ID 1105272
Category Recording
Type Field Visit
Permalink http://canmore.org.uk/event/1105272
The Cleaven Dyke is aligned NW-SE and extends for a distance of about 2.3km across level ground to the N of the confluence of the Rivers Tay and Isla. Upstanding traces survive in woodland for about 1.73km (NO 1566 4087 to 1721 3997), the remainder now being known from soil-and cropmarks. There is no evidence that it originally extended as far to the SE as the probable square barrow at Hallhole (NO13NE 10) that is shown on the early maps of Stobie and McOmie or implied by Pennant, nor that it extended beyond the present NW terminal.
The Dyke is neither straight nor totally regular, but displays minor changes of alignment at several points along its course, and is interrupted by an original gap at NO 1705 4007. The gap through which the A93 road passes (NO 168 402) may also be of early origin, while the thickening of the bank at the NW end of the upstanding section may mark the SE side of a further gap.
The Dyke comprises a bank flanked on each side by a broad berm and a single ditch. The bank measures between 8m and 10m in thickness for most of its length, and up to about 1.8m high, but is appreciably larger at its NW terminal, where it is some 16m thick. In the light of sections cut in 1993, earlier records (J Abercromby 1902; I A Richmond 1940; H Adamson and D Gallagher 1986) of its structure and composition appear to be misleading.
The ditches are set between 8 and 9m from the bank and appear to be of varying widths, particularly in the SE portion, as revealed by cropmarks. They were perhaps dug in sections and were in places up to 6.5m broad.
To the W of the A93 (where the undergrowth is less dense than elsewhere along the Dyke) there are traces of rig-and-furrow cultivation between the bank and the ditches. The ridges are most clearly visible to the S of the bank and are of two phases, the earlier aligned roughly at right-angles to the bank and in places overriding it, while the rigs of the later phase run parallel to the bank. Traces of various trackways and field-banks can also be seen cutting across the crown of the Dyke. There is no direct evidence for the date of the Dyke, but study of the soils and pollen from the most recent section suggests that it was constructed in land that had already seen one or more phases of clearance and cultivation. Due to its apparent straightness and regularity, and its proximity to the Roman fortress at Inchtuthil (NO13NW 5.00) the Dyke was formerly considered to be a Roman defensive work (T Pennant 1776) or political boundary (I A Richmond 1940), but better analogies may be found among Neolithic cursuses.
Visited by RCAHMS (AW/SH) June 1992.
T Pennant 1776; J Stobie 1783; J McOmie 1784; J Abercromby 1902; I A Richmond 1940; L F Pitts and J K St Joseph 1985; H Adamson and D Gallagher 1986; G S Maxwell 1989.
