Boltby Scar Hillfort is sited where a westwards bulge in the edge of the Hambleton Hills escarpment coincides with an area of higher ground. The fort is thought probably to be early Iron Age in date (in existence by perhaps 500–400BC) but uncertainty exists both relating to the nature and chronology of its origins and development, and to its relationship with the Cleave Dyke. The latter runs approximately 150m to the east of the fort but there appears to be a break (for at least 700m) in its length at precisely this location. The latter appears to provide access for the fort through the line of the dyke to the land to the east. In addition, this arrangement may be mirrored approximately 3km to the south by the sudden termination of the southern end of the Cleave Dyke in an unexplained position approximately 900m north of the hillfort at Roulston Scar. This may also be due to the need to leave similar access to the east. This layout may suggest, therefore, that both hillforts and the Cleave Dyke are contemporary and part of a single territorial system.
The defences of the hillfort at Boltby Scar, with an entrance (probably not original) in the NE sector, were laid out in such a way that the circuit coincided with and actually enclosed at least two round barrows, burial mounds from the early Bronze Age (part of a larger cemetery from over a thousand years earlier), one of which still survives as a prominent earthwork. These and the other round barrows in the area reinforce the importance of this landscape to the early prehistoric peoples living round and about, significance apparently continued in the Iron Age by the construction of the hillforts and the Cleave Dyke.
The defences consisted of a rampart, external ditch and outer counterscarp bank (as noted in an excavation archive photograph by Margaret Smith). Approximately one third of the defences of the fort still survive on the outside of the field boundary where it adjoins Boltby Scar and through which the Cleveland Way runs. The rampart is up to 4m wide and 1m high; the ditch up to 3.5m wide and 1m deep. This surviving part of the hillfort, together with the narrow fringe of the escarpment which extends for 400m to the NNE, is also important ecologically in that it represents a small vestige of the original moorland which covered this area and survived around the hillfort even after the Second World War. Beyond the dividing wall, within the farmland, the bank and ditch (and the mound of the second round barrow) were levelled in 1961, despite having been recognised as nationally important and legally protected as a Scheduled Monument since 1938, and are now only visible as soil, or crop, marks.
The site was the subject of excavations in the 1930s by George Willmot (whose excavation notes have been transcribed by Margaret Smith). The investigation comprised four trenches within the east side of the interior of the fort, and two trenches across the defences. The excavation of the interior recovered four sherds of pottery, reported to be Iron Age in date, but revealed no evidence of internal structures. However, a further investigation in the same decade by R. W. Crosland and a WEA group recorded a roughly paved area c.3m square partly under the N-S wall which divides the site. Willmot recorded the rampart as c.4.25m wide, composed of earth, yellow sand and small stones from the ditch which was c.3.65m wide and c.1.2m deep. From the old ground surface beneath the rampart were discovered two ‘featureless’ pottery sherds and the famous pair of gold “basket earrings”, perhaps now more correctly interpreted as decorations for tresses/braids of hair (c.f. the ‘Amesbury archer’), dated to the Early Bronze Age Beaker period. However, their location beneath the rampart may be entirely fortuitous and relate to the area of the Early Bronze Age cemetery which overlaps with the hillfort. Larger stones on the top and inner side of the rampart were suggested to derive from the bottom of the ditch. Below the rampart in a second trench was a layer c.0.23-0.3m thick of dark grey clay, charcoal and burnt stones, later interpreted as the old ground surface prior to the rampart’s construction.
Within the WSW sector of the surviving portion of the hillfort is recorded a small sub-rectangular ditched platform of unknown date. This is currently overgrown with scrubby vegetation and hard to examine clearly but its date and significance are currently unknown. Clarification of the surviving earthwork remains of the hillfort was achieved by a detailed topographic survey, supported by a programme of geophysical survey (subject to the limitations of available techniques on the local geology) which examined the interior of the fort – both the ploughed and unploughed areas – and other surrounding areas which are considered important for information to clarify potential relationships with the Cleave Dyke and associated monuments.
The management proposal for this site is to remove the modern infill from the external ditch of the monument in order to reconstruct a facsimile of the rampart bank to the approximate dimensions which were in existence prior to levelling (in 1961). The exact reconstruction technique and extent will be informed by the excavation.
The planned programme of works at Boltby Scar hillfort constitute a much longer term vision for the whole of the ‘Cleave Dyke Landscape’. This vision is under continued development and evolution.
The excavation will involve the examination of three sections across the levelled bank and ditch to establish the original surface of the ditch prior to 1961, to establish whether any traces of the base of the rampart or related structural elements still survive and, in one trench, to investigate the original nature and stratigraphic sequences of the make-up of the ditch. The latter excavation would be for research purposes in order to attempt to acquire material which could help date and clarify the origins and construction sequence of the fort, and potentially help to shed light on its relationship with the Cleave Dyke.