Monument record MDO3248 - Linear dyke on Bronkham Hill, Winterborne St Martin

Linear dyke running across Bronkham Hill, probably Romano-British or later in origin. Also visible as a fragmentary double linear earthwork on aerial photographs

Linear Dyke, on Bronkham Hill (SY 62558680 to 62938675). Running athwart the Ridgeway and cutting over round barrow (MDO3147) is a single bank at most 14ft across and 1 1/2ft high, with a ditch on the North. Short erratic stretches link solution hollows - but do not run down into them as do later banks - from a point about 230 yds. The dyke climbs the South face of the ridge (in the parish of Portesham) and is crossed by the present stone wall on the Winterborne St Martin boundary and by another running up to the boundary. The bank appears to consist solely of the gravel of the underlying Bagshot Beds. The barrow is the only feature which clearly ante-dates it, and the fact that it mutilates the barrow strongly suggests a Romano-British or, probably, later origin, while its disregard for the parish boundary could point to a date before the formation of the parishes. <1>

At the west end the feature is visible as a weak ditch with a poorly-formed bank on either side; overall width 8.5m., with ditch 0.4m. deep and banks 0.2m. high on the uphill side and 0.3m., high on the downhill. The best-preserved section of the dyke occurs at SY 62748680 where it crosses the crest of the ridge. On the north face of the ridge the ditch is formed on the southern uphill, side; it is here poorly defined, on average 6.0m. wide and 0.5m. deep with a fragmentary bank up to 0.3m. high. Long sections of the dyke now traverse through inpenetrable gorse bushes; elsewhere it crosses open heath. <2>

Also visible as a fragmentary double linear earthwork on aerial photographs <3-6>. This site was digitally plotted during the South Dorset Ridgeway Mapping Project.

<1> Royal Commission on Historical Monuments (England), 1970, An Inventory of Historical Monuments in the County of Dorset, Volume II (South East) Part 3, 519 (Monograph). SDO150.

'(145) LINEAR DYKE, on Bronkham Hill (SY 68 NW; 62558680 to 62948675; Plate 209). Running athwart the Ridgeway and cutting over round barrow Winterborne St. Martin (47) is a single bank, at most 14 ft. across and 1½ ft. high, with a ditch on the N. Short erratic stretches link solution hollows— but do not run down into them as do later banks—from a point about 230 yds. W. of barrow (47) to about 185 yds. E. of it. The dyke climbs the S. face of the ridge (in the parish of Portesham), and is crossed by the present stone wall on the Winterborne St. Martin boundary and by another running up to the boundary. The bank appears to consist solely of the gravel of the underlying Bagshot Beds. The barrow is the only feature which clearly ante-dates it, and the fact that it mutilates the barrow strongly suggests a Romano-British or, probably, later origin, while its disregard for the parish boundary could point to a date before the formation of the parishes.'

<2> Barton, J G, Various, Field Investigators Comments JGB, F1 JGB 12-MAR-80 (Unpublished document). SDO11900.

<3> Royal Air Force, 22-1-1948, RAF/CPE/UK/2431 3295-6 (Aerial Photograph). SDO11932.

<4> 14-4-1957, CUCAP (UM64) (Aerial Photograph). SDO11944.

<5> Royal Air Force, 04-NOV-1946, RAF/CPE/UK/1824 3293-5 (Aerial Photograph). SDO11893.

<6> unknown date, NMR SY6286/2 (CCC 1755/5900) (Aerial Photograph). SDO11945.

<7> Royal Commission on Historic Monuments, Externally held archive: RCH01/093 RCHME Inventory: Dorset II (South-East) (Unpublished document). SDO17434.

<8> National Record of the Historic Environment, 452501 (Digital archive). SDO14739.

Record last edited

Dec 30 2022 3:43PM