Atlas of Hillforts of Britain and Ireland

WA1967 Trwyn-y-Castell, Pembrokeshire (Trwyn y Castell; Trwyn)

Satellite Imagery

Satellite Imagery

HER:  Dyfed 2733 (None)

NMR:  SM 73 SE (102710)

SM:  None

NGR:  SM 7940 3149

X:  179400  Y:  231490  (OSGB36)

Summary

Small and complex coastal promontory fort located on prominent W-facing, rocky promontory immediately N of Abereiddi Bay on N coast. Promontory 270m long jutting out into Irish Sea. Sea cliffs to N, S and W, landward to coastal plateau on E. Multivallate, and eroded on S, defences cut off the promontory c. 140m from tip to give enclosed area c. 110m by 60m, with area estimated at c. 0.66ha. Defences difficult to determine and have been investigated by DAT. They consist of four or five banks and ditch. Outer bank on E most massive, with no outer ditch, but to c. 4m wide and over 3m above a rock-cut ditch on its inner W side. Second bank to W consists of unexcavated bedrock between two ditches, rather than built bank. Two more sets of slight bank and ditch to W then gap of 20m. Here promontory widens out and protected by a further bank running along a natural rise. Entrance possibly on S side, where all banks stop short of sea cliff. N slope steep and here quarrying, but to W several slight platforms cut into slope may be hut sites. Post medieval Abereiddi Tower to W at highest point of promontory. Ditch running N-S c. 140m E of defences modern quarrying and further to E massive modern quarrying isolates whole of rpomontory from mainland. Site under rich coastal grassland with bare rock exposed. On 1st Ed. OS map (1889). Minimal investigations, undated.

Status

Citizen Science:  ✗

Reliability of Data:  Confirmed

Reliability of Interpretation:  Confirmed

Location

X:  -580057  Y:  6788929  (EPSG: 3857)

Longitude:  -5.210744005981817  Latitude:  51.93803635823904  (EPSG:4326)

Country:  Wales

Current County or Unitary Authority:  Pembrokeshire

Historic County:  Pembrokeshire

Current Parish/Community/Council/Townland:  Llanrhian

Monument Condition

S side eroded making interpretation difficult. Quarrying to N slope. Post medieval Abereiddi Tower to W at highest point of promontory. Pembrokeshire Coast Path to E. Modern quarrying to E isolates whole of promontory from mainland.

Condition:
Extant   ✓
Cropmark   ✗
Likely Destroyed   ✗

Land Use

Site under coastal grassland with bare rock exposed. Post medieval Abereiddi Tower to W at highest point of promontory. Quarrying.

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

Small and complex coastal promontory fort located on prominent, W-facing, rocky promontory immediately N of Abereiddi Bay on N coast.Promontory 270m long jutting out into Irish Sea. Sea cliffs to N, S and W, landward to coastal plateau on E.

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:  Coastal promontory

Aspect:
North   ✗
Northeast   ✗
East   ✗
Southeast   ✗
South   ✗
Southwest   ✗
West   ✓
Northwest   ✗
Level   ✗

Altitude:  35.0m

Boundary

N/A


Dating Evidence

None

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

On 1st Ed. OS map (1889). Field Observation OS 1966. Field Observation Arch Survey NT1989. Field Observation DAT 1994, 1996, 2006. Cambria Archaeology defended enclosures survey 2006-2007.

Investigations:
1st Identified Map Depiction (1889):   OS map.
Other (1966):   Field observation OS.
Other (1989):   Field Observation Arch Survey NT.
Other (None):   Field observation DAT.
Other (None):   Cambria Archaeology defended enclosures survey.

Interior Features

To W several slight platforms cut into slope may be hut sites.

Water Source

None

Source:
None   ✓
Spring   ✗
Stream   ✗
Pool   ✗
Flush   ✗
Well   ✗
Other   ✗

Surface

To W several slight platforms cut into slope may be hut sites.

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

None

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

Entrances

Entrance possibly on S side, where all banks stop short of sea cliff.

Total Number of Breaks Through Ramparts:  
1:   None

Number of Possible Original Entrances:  
2:   None

Guard Chambers:  ✗

Chevaux de Frise:  ✗

Entrances:
1. Simple Gap (South east):   None

Enclosing Works

Four or five banks and ditch. Outer bank on E most massive, with no outer ditch, but to c. 4m wide and over 3m above a rock-cut ditch on its inner W side. Second bank to W consists of unexcavated bedrock between two ditches, rather than built bank. Two more sets of slight bank and ditch to W then gap of 20m. Here promontory widens out and protected by a further bank running along a natural rise.

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

Total Footprint Area:  Noneha.

Ramparts

None

Multi-period Enclosure System:
✗   Estimated area.

Ramparts Form a Continuous Circuit:
✗   Four or five banks defined.

Number of Ramparts:  
NE Quadrant:   5
SE Quadrant:   5
SW Quadrant:   0
NW Quadrant:   0
Total:   5

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

Possible rubble bank using natural bedrock along line.

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:
✓   Four or five rock-cut ditches.

Number of Ditches:  5

Annex:
✗   None

References

Murphy, K., Ramsey, R., Poucher, P. and Page, M. 2007. A Survey of Defended Enclosures in Pembrokeshire, 2006-2007: Gazetteer of Ordnance Survey Grid Squares SM73, SM83 and SM93, Cambria Archaeology Report No. 2007/01, Project Record No. 54269, Llandeilo: Cambria Archaeology.



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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