Ancient Monuments

History on the Ground

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Castell Caer Lleion

A Scheduled Monument in Conwy, Conwy

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Latitude: 53.2826 / 53°16'57"N

Longitude: -3.8616 / 3°51'41"W

OS Eastings: 275981

OS Northings: 377799

OS Grid: SH759777

Mapcode National: GBR 1ZGG.RZ

Mapcode Global: WH53Z.NRBB

Entry Name: Castell Caer Lleion

Scheduled Date:

Source: Cadw

Source ID: 3422

Cadw Legacy ID: CN012

Schedule Class: Defence

Category: Hillfort

Period: Prehistoric

County: Conwy

Community: Conwy

Traditional County: Caernarfonshire


Hillfort on Conwy Mountain (Mynydd y Dref), also known as Castell Caer Seion or Lleion. The summit of a ridge of rhyolite is enclosed by a single rampart, with more complex works protecting a smaller fortified area at the W end.

Within the fort 58 round hut foundations are visible as levelled platforms, including 7 in the smaller enclosure.

The large enclosure also contains a rectangular levelled platform, on the N slopes 430ft NNE from the main entrance; 600ft NE from the entrance is a circular pit of about 4ft diameter with a trench leading into it from the NE - in plan resembling a corn-drying kiln. There are possible traces of others.

The detailed structural history of the site remains open to several widely different interpretations. It appears certain that the existing remains represent two or more periods of construction, during at least one of which both the enclosures were occupied together, although there is no indication of direct access from one to the other, and indeed the small enclosure seems to have been designed to resist attack from within the large enclosure as well as from outside.

The site is traditionally associated with Maelgwn, but there is no other evidence either way as to a sixth-century occupation. The main structure belongs to the pre-Roman Iron Age.

The monument is of national importance for its potential to enhance our knowledge of prehistoric settlement and defence. It retains significant archaeological potential, with a strong probability of the presence of associated archaeological features and deposits. The structures themselves may be expected to contain archaeological information concerning chronology and building techniques.

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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