Blackbury Castle hillfort

Reasons for Designation

Large univallate hillforts are defined as fortified enclosures of varying shape, ranging in size between 1ha and 10ha, located on hilltops and surrounded by a single boundary comprising earthworks of massive proportions. They date to the Iron Age period, most having been constructed and used between the fourth century BC and the first century AD, although evidence for earlier use is present at most sites. The size of the earthworks reflects the ability of certain social groups to mobilise the labour necessary for works on such a monumental scale, and their function may have had as much to do with display as defence. Large univallate hillforts are also seen as centres of redistribution, both for subsistence products and items produced by craftsmen. The ramparts are of massive proportions except in locations where steepness of slope precludes easy access. They can vary between 6m and 20m wide and may survive to a height of 6m. The ditches can measure between 6m and 13m wide and between 3m and 5m deep. Access to the interior is generally provided by one or two entrances which often take the form of long passages formed by inturned ramparts and originally closed by a gate located towards the inner end of the passageway. The entrance may be flanked by guardrooms and/or accompanied by outworks. Internal features included timber or stone round houses; large storage pits and hearths; scattered postholes, stakeholes and gullies; and square or rectangular buildings supported by four to six posts, often represented by postholes, and interpreted as raised granaries. Large univallate hillforts are rare with between 50 and 100 examples recorded nationally. Most are located within southern England where they occur on the chalklands of Wessex, Sussex and Kent. The western edge of the distribution is marked by scattered examples in north Somerset and east Devon, while further examples occur in central and western England and outliers further north. Within this distribution considerable regional variation is apparent, both in their size, rampart structure and the presence or absence of individual components. In view of the rarity of large univallate hillforts and their importance in understanding the organisation and regional structure of Iron Age society, all examples with surviving archaeological remains are believed to be of national importance.

Blackbury Castle hillfort survives well and is known from part excavation to contain archaeological evidence relating to the occupation of this area during the Iron Age. The entrance passage together with the associated triangular enclosure represent an unusual group of earthworks with no precise recorded parallels.

Details

This monument includes a large Iron Age univallate hillfort known as Blackbury Castle which straddles an east to west spur leading from the Broad Down plateau and overlooks valleys formed by tributaries of the River Coly. The hillfort has a bank and associated outer ditch surrounding an oval internal area measuring 186m east to west by 90m north to south. The rampart is composed of an unrevetted flint rubble bank measuring up to 10m wide, 1.8m high internally and 4.8m high externally. The outer ditch measures up to 12m wide and 1.1m deep. The entrance to the hillfort lies on the southern side, is slightly out-turned and originally contained a timber gateway which was probably bridged. At a later date, a triangular outer defence including two separate lengths of ditch and rampart were added together with a narrow funnel shaped entrance passage measuring 50m long and defined on either side by 2.5m wide and 1m high banks. Gaps in the northern, eastern and western circuit of the hillfort are considered to represent the result of more recent activity and are therefore probably not original features. Within the interior of the fort, are two rectangular building platforms built up against the rampart face. The eastern structure measures 10.5m long, 7.3m wide and stands up to 0.7m high, whilst the western one is 9m long, 6m wide and 0.4m high. These features probably represent the site of medieval or post medieval buildings and may be connected with some of the more recent breaches in the rampart. The hillfort was partly excavated between 1952 and 1954 by the Devon Archaeological Society and this work revealed the site of a hut, an associated palisade, various trenches, a cooking pit, oven, a hoard of slingstones and a heap of clay. Finds from the excavation included numerous sherds of Iron Age pottery, 15 lumps of iron slag, over a thousand slingstones, four whetstones, two spindle whorls, two bronze fragments and four worked flints. The monument is in the care of the Secretary of State.

MAP EXTRACT The site of the monument is shown on the attached map extract. It includes a 2 metre boundary around the archaeological features, considered to be essential for the monument's support and preservation.

Legacy

The contents of this record have been generated from a legacy data system.

Legacy System number:

24116

Legacy System:

RSM

Sources

Books and journals
Dyer, J, South England Archaeological Guide, (1973), 55
Grinsell, LV, Discovering Regional Archaeology South Western England, (1970), 22
Grinsell, LV, Discovering Regional Archaeology South Western England, (1970), 21-22
Hawkes, J, The Shell Guide to British Archaeology, (1986), 126
Young, A, Richardson, K M, Devon Archaeological Society Proceedings in Report on the Excavations at Blackbury Castle, Vol. 5, (1958), 43-67

Other
Devon County Sites and Monuments Register, SY19SE47, (1993)
Devon County Sites and Monuments Register, SY19SE47-01, (1987)
MPP fieldwork by S. Gerrard, (1994)
1:2500, Ordnance Survey, Ordnance Survey Plan SY 1892, (1958)

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