Atlas of Hillforts of Britain and Ireland

SC2838 Mainland, Point of Onston, Orkney (Diamond Cottage)

Satellite Imagery

Satellite Imagery

HER:  Orkney Islands 1710 (None)

NMR:  HY 21 SE 22 (1710)

SM:  5871

NGR:  HY 2828 1179

X:  328284  Y:  1011791  (OSGB36)

Summary

An earthwork comprising twin concentric ditches and banks is drawn in a regular arc across the low-lying tip of Onston Point. The ditches are both about 3m broad, lying to either side of a low medial bank about 0.6m high, and the second low bank stands on the counterscarp of the outer ditch. There are several gaps along its line, but aerial photographs suggest a slight misalignment to either side of one 40m E of the W shore, perhaps indicating this is original, though the OS surveyor in 1966 suggested there was an entrance causeway near the NE shore. The roughly triangular interior is featureless and measures 130m from N to S, tapering from a maximum 80m transversely immediately to the rear of the earthwork to a point in the shallows of the loch (0.66ha). At the NE end of the perimeter, however, aerial photographs also show traces of a line of stones extending N in a straight line for a distance of at least 60m beneath the water, possibly indicating that the enclosed area on dryland was once considerably larger. The date and purpose of this promontory work are unknown.

Status

Citizen Science:  

Reliability of Data:  Confirmed

Reliability of Interpretation:  Confirmed

Location

X:  -361738  Y:  8177647  (EPSG: 3857)

Longitude:  -3.24954857430822  Latitude:  58.987321466960424  (EPSG:4326)

Country:  Scotland

Current County or Unitary Authority:  Orkney Islands

Historic County:  Orkney

Current Parish/Community/Council/Townland:  Stenness

Monument Condition

None

Condition:
Extant  
Cropmark  
Likely Destroyed  

Land Use

None

Current Use:
Woodland  
Commercial Forestry Plantation  
Parkland  
Pasture (Grazing)  
Arable  
Scrub/Bracken  
Bare Outcrop  
Heather/Moorland  
Heath  
Built-up  
Coastal Grassland  
Other  

Landscape

Hillfort Type

None

Type:
Contour Fort  
Partial Contour Fort  
Promontory Fort  
Hillslope Fort  
Level Terrain Fort  
Marsh Fort  
Multiple Enclosure Fort  

Topographic Position

Position:
Hilltop  
Coastal Promontory  
Inland Promontory  
Valley Bottom  
Knoll/Hillock/Outcrop  
Ridge  
Cliff/Plateau-edge/Scarp  
Hillslope  
Lowland  
Spur  

Dominant Topographic Feature:  None

Aspect:
North  
Northeast  
East  
Southeast  
South  
Southwest  
West  
Northwest  
Level  

Altitude:  5.0m

Boundary

N/A


Dating Evidence

In the absence of modern excavation, there are neither stratified artefacts nor radiocarbon dates to provide a chronology for the defences.

Reliability:  D - None

Principal Activity:
Pre 1200BC  
1200BC - 800BC  
800BC - 400BC  
400BC - AD50  
AD50 - AD400  
AD400 - AD 800  
Post AD800  
Unknown  

Other Activity:
Pre Hillfort:   None
Post Hillfort:   None

Evidence:No related records

Investigation History

None

Investigations:
1st Identified Written Reference (1907):   First noted in The Orcadian 19 Oct 1907
Earthwork Survey (1928):   Plan and description (RCAHMS 1946, ii, 298, no.873, fig 373; ORD 62/1-2)
Excavation (1960):   Trench by FT Wainwright (Lamb 1980, 78)
Other (1966):   Surveyed at 1:2500 by the OS
Other (1970):   Description by Raymond Lamb (1980, 78)
Other (1994):   Scheduled
Geophysical Survey (2007):   Geophysics Unit, Orkney College

Interior Features

Featureless

Water Source

None

Source:
None  
Spring  
Stream  
Pool  
Flush  
Well  
Other  

Surface

None

Interior Features (Surface):
No Known Features  
Round Stone Structures  
Rectangular Stone Structures  
Curvilinear Platforms  
Other Roundhouse Evidence  
Pits  
Quarry Hollows  
Other  

Excavation

None

Interior Features (Excavation):
No Known Excavation  
Pits  
Postholes  
Roundhouses  
Rectangular Structures  
Roads/Tracks  
Quarry Hollows  
Other  
Nothing Found  

Geophysics

None

Interior Features (Geophysics):
No Known Geophysics  
Pits  
Roundhouses  
Rectangular Structures  
Roads/Tracks  
Quarry Hollows  
Other  
Nothing Found  

Finds

None

Interior (Finds):
No Known Finds  
Pottery  
Metal  
Metalworking  
Human Bones  
Animal Bones  
Lithics  
Environmental  
Other  

Aerial

NO APPARENT FEATURES

Interior Features (Aerial):
APs Not Checked  
None  
Roundhouses  
Rectangular Structures  
Pits  
Postholes  
Roads/Tracks  
Other  

Entrances

See main summary

Total Number of Breaks Through Ramparts:  
2:   None

Number of Possible Original Entrances:  
2:   None

Guard Chambers:  

Chevaux de Frise:  

Entrances:
1. Simple Gap (South):   Misalignment of particularly the outer ditch
2. Simple Gap (South east):   Causeway

Enclosing Works

Two ditches with external banks cutting off a promontory

Enclosed Area:
Area 1:   0.66ha.
Total:   0.66ha.

Total Footprint Area:  Noneha.

Ramparts

None

Multi-period Enclosure System:
✗   None

Ramparts Form a Continuous Circuit:
✗   None

Number of Ramparts:  
NE Quadrant:   0
SE Quadrant:   2
SW Quadrant:   0
NW Quadrant:   0
Total:   2

Morphology

Current Morphology:
Partial Univallate  
Univallate  
Partial Bivallate  
Bivallate  
Partial Multivallate  
Multivallate  
Unknown  

Detailed Morphology:
Partial Univallate  
Univallate  
Partial Bivallate  
Bivallate  
Partial Multivallate  
Multivallate  

Surface Evidence

None

Enclosing Works (Surface):
None  
Earthen Bank  
Stone Wall  
Rubble  
Wall-walk  
Evidence of Timber  
Vitrification  
Other Burning  
Palisade  
Counter Scarp Bank  
Berm  
Unfinished  
Other  

Excavated Evidence

None

Enclosing Works (Excavation):
None  
Earthen Bank  
Stone Wall  
Murus Duplex  
Timber-framed  
Timber-laced  
Vitrification  
Other Burning  
Palisade  
Counter Scarp Bank  
Berm  
Unfinished  
No Known Excavation  
Other  

Other

Gang Working:
✗   None

Ditches:
✓   None

Number of Ditches:  2

Annex:
✗   None

References

Lamb, R G (1980) Iron Age promontory forts in the Northern Isles. Brit Archaeol Rep, British Ser 79. BAR: Oxford

RCAHMS (1946) The Royal Commission on the Ancient and Historical Monuments of Scotland. Twelfth report with an inventory of the ancient monuments of Orkney and Shetland, 3v. HMSO: Edinburgh



Terms of Use

This work is licensed under CC BY-SA 4.0 and should be cited as:

Lock, Gary and Ralston, Ian. 2024. Atlas of Hillforts of Britain and Ireland. Available at: https://hillforts.arch.ox.ac.uk


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