Ancient Monuments

History on the Ground

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Cist Cerrig Burial Chamber & Cup Marked Rock

A Scheduled Monument in Porthmadog, Gwynedd

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Latitude: 52.9233 / 52°55'23"N

Longitude: -4.1681 / 4°10'5"W

OS Eastings: 254339

OS Northings: 338407

OS Grid: SH543384

Mapcode National: GBR 5N.MV9M

Mapcode Global: WH55K.YSBB

Entry Name: Cist Cerrig Burial Chamber & Cup Marked Rock

Scheduled Date:

Source: Cadw

Source ID: 3474

Cadw Legacy ID: CN118

Schedule Class: Religious, Ritual and Funerary

Category: Chambered tomb

Period: Prehistoric

County: Gwynedd

Community: Porthmadog

Traditional County: Caernarfonshire


The monument comprises the remains of a chambered tomb, dating to the Neolithic period (c. 4,400 BC - 2,900 BC). Chambered tombs were built and used by local farming communities over long periods of time. There appear to be many regional traditions and variations in shape and construction.

The three orthostats are arranged in a 'H' formation and are the remains of a portal dolmen; apart from stones piled immediately around the base, there is no sign of an associated mound. The two side stones are each 2.3m high, the northern stone being 1.8m wide and the southern stone 1.6m wide. The central blocking stone is 2.1m in height and 1m in width. Twenty-three metres to the east of the uprights is a series of cup-marks on a rock outcrop. Ten cup-marks of varying size and clarity can be seen arranged in a line 2.3m in length, with a further two offset to the right of the line.

The monument is of national importance for its potential to enhance our knowledge of prehistoric burial and ritual. The monument is an important relic of a prehistoric funerary and ritual landscape and retains significant archaeological potential, with a strong probability of the presence of both intact burial or ritual deposits and environmental and structural evidence, including a buried prehistoric land surface. Chambered tombs may be part of a larger cluster of monuments and their importance can be enhanced further by their group value.

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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