1. NAR SH39NE1

2. Anglesey Inventory (1937) pp 37-38

DINAS GYNFOR, a large promontory fort on the N. sea-coast, 1 m. N.E. of the parish church. The headland, with a maximum height of 200 ft., is bounded on three sides by precipitous cliffs to the sea, and on the landward side by a steep slope to a marshy valley, running between two inlets of the sea. The main defence is drawn across the top of the landward slope, and consists of a wall of limestone blocks; there is an irregular quarry-ditch inside. On the N.W. the wall encloses a natural terraced area backed by an outcrop, and then runs S.E. along the crest of the slope for about 250 yards, where it is broken by an original incurved entrance approached by a trackway running diagonally up the hillside. The wall continues 100 yards S.E. to a natural citadel of rock, where another entrance is formed by a naturally defended gully leading up from Porth Cynfor, with remains of a defensive wall at its base. The main wall is carried on for 50 yards N.E. of this gully and then dies out against the precipitous cliff. A second line of defence, roughly parallel to the first and lower down the slope, runs from the E. side of the incurved entrance, looping round so as to protect the approach and running N.W., dying out where the slope becomes precipitous. (Arch. Camb., 1876, pp. 103-8; Condition—Fair, somewhat mutilated by quarrying.

2. National Trust: Described as a large promontory fort on the N sea-coast 1 mile NE of the parish church. The headland, with a maximum height of 200ft, is bounded on 3 side by precipitous cliffs to the sea, and on the landward side by a steep slope to a marshy valley, running between 2 inlets of the sea. The main defence is drawn across the top of the landward slope, and consists of a wall of limestone blocks; there is an irregular quarry-ditch inside. On the NW the wall encloses a natural terraced area backed by an outcrop, and then runs SE along the crest of a slope for about 250yds, where it is broken by an original incurved entrance approached by a trackway running diagonally up the hillside. The wall continues 100yds SE to a natural citadel of rock, where another entrance is formed by a naturally defended gully leading up from Porth Cynfor, with remains of a defensive wall at its base. The main wall is carried on for 50yds NE of this gully and then dies out against the precipitous cliff.

A second line of defence, roughly parallel to the first and lower down the slope, runs from the E side of the incurved entrance, looping round so as to protect the approach and running NW dying out where the slope becomes preciptious. (RCAHM Inventory of Anglesey, 1937).That portion of the fort that belongs to the National Trust lies on the NE and seaward side, gently sloping land down to steep cliffs at the coast. There appeared to be no visible remains of ramparts or habitation sites within the area; more significant remains are found on the more heavily defended landward side to SW.

Source: Survey of Anglesey (2004) Peter Muckle. for the National Trust
John Latham RCAHMW 25 July 2004

3. Cadw: Scheduled Monument Entry for AN038

The following provides a general description of the Scheduled Monument. The monument comprises the remains of a promontory fort, which probably dates to the Iron Age period (c. 800 BC - AD 43). It is bounded on three sides by the sea and on the landward side by a steep slope to a marshy valley, running between two inlets of the sea. The main defence is drawn across the top of the landward slope, and consists of a wall of limestone blocks; there is an irregular quarry-ditch inside. On the NW the wall encloses a natural terraced area backed by an outcrop, and then runs SE along the crest of the slope for about 228m, where is it broken by an original in-curved entrance approached by a trackway running diagonally up the hillside. The wall continues 91m SE to a natural citadel of rock, where another entrance is formed by a naturally defended gully leading up from Porth Cynfor, with remains of a defensive wall at its base. The main wall is carried on for 45m NE of this gully, and then dies out against the precipitous cliff. A second line of defence, roughly parallel with the first and lower down the slope, runs from the E side of the in-curved entrance, looping round so as to protect the approach, and running NW, dying out where the slope becomes precipitous. The bank at the base of the second entrance consists of a length of stone bank 2-3m wide and 1m high. The interior is very rocky and has been much damaged by quarrying. No habitation sites are visible. Also within the scheduled area lie some industrial remains at Porth Llanlleiana, connected with the china clay industry, and on top of the fort is a tower commemorating the coronation of King Edward VII.

4. Royal Commission. Visited by Toby Driver and Louise Barker for the Royal Commission, 17th Sept 2024

The remains of the hillfort are much as described by Cadw, although the defences of the fort are now heavily overgrown by dense vegetation and undergrowth making them difficult to follow. Recent (2023) 1m LiDAR coverage provides a very useful Digital Terrain Model of the fort to show the built features below the vegetation.

Although the hillfort has been extensively quarried for the nearby china clay industry at Porth Llanlleiana (NPRN 404312), records also show the presence of copper at this coastal inlet. Copper deposits and coastal access may be two reasons why this particular headland was chosen for fortification in later prehistory. It may also have been occupied in early Medieval times.

Toby Driver, RCAHMW, September 2024.

Sources:
Lynch 'Prehistoric Anglesey' (1970), 233-36

RCAHMW (M). 1937. An Inventory of the Ancient Monuments in Anglesey. HMSO, London. 

Williams in Archaeologia Cambrensis 4th series 7 (1876), 103-8