Ancient Monuments

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Holyhead Mountain Hut Circles

A Scheduled Monument in Trearddur, Isle of Anglesey (Ynys Môn)

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Latitude: 53.3053 / 53°18'19"N

Longitude: -4.6839 / 4°41'2"W

OS Eastings: 221265

OS Northings: 382064

OS Grid: SH212820

Mapcode National: GBR GMTY.THD

Mapcode Global: WH31B.05VY

Entry Name: Holyhead Mountain Hut Circles

Scheduled Date:

Source: Cadw

Source ID: 2512

Cadw Legacy ID: AN016

Schedule Class: Domestic

Category: Unenclosed hut circle settlement

Period: Prehistoric

County: Isle of Anglesey (Ynys Môn)

Community: Trearddur

Traditional County: Anglesey


The monument consists of an area of later Prehistoric settlement features, generally stone founded roundhouses, occupying a natural shelf or terrace below the south-eastern flank of Holyhead Mountain. The scheduled area occupies some 8 ha of a 25 m-wide natural terrace which contains a series of stone-built structures. These structures are of two main types: round huts and sub-rectangular chambers. There are 13 round huts, some with entrance passages, varying in diameter from 3.8 m to 8 m. They are clearly visible and have been cleared of overlying vegetation and consolidated for public display. The walls are of dry-stone construction with few orthostats and are generally 0.5 - 1 m high and 1 - 1.25 m wide.

The rectangular structures vary between 4 m and 4.75 m long, 1.25 and 1.9 m wide, and are about 1 m deep. They are part sunken, with rounded corners, and, with one exception, are also of dry, laid stone, as opposed to orthostatic, construction. The exception (Hut L) is largely of orthostatic construction, the stones lining the inner face being 1.25 m high. One of the structures (Hut N) is 2.25 m square, the walls are 0.7 m high, and a large paving slab can be seen at the rear. The round huts have their entrances on the south east side, whereas the rectangular structures tend to have an entrance on the north-north-west side, the exception again being Hut L which faces east-north-east.

The remains of a terraced field system can be seen underlying the present fields on the slopes below the settlement. To the north, on the slopes above the settlement, is a complex of field boundaries which could also be associated with this settlement. These lie entirely outside the scheduled area.

The site has been excavated on three occasions, by W O Stanley in the 1860s, by the Office of Works in 1912-13, and by the Welsh Office during the years 1978-82. The most important results to come out of the last excavations were the dating of the settlement to the late first millennium BC, with evidence of activity on the site from the late third millennium BC and also the first century AD. It has also been shown that, rather than being an open settlement, it was a cluster of homesteads with enclosures, interspersed with isolated huts.

The monument is of national importance for its potential to enhance our knowledge of later prehistoric defensive organisation and settlement. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. The structure itself may be expected to contain archaeological information concerning chronology and building techniques, together with a strong probability of environmental evidence.

The scheduled area comprises the remains described and areas around them within which related evidence may be expected to survive.

Source: Cadw

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