Ancient Monuments

History on the Ground

This site is entirely user-supported. See how you can help.

Pen-y-Rhiw Round Cairn

A Scheduled Monument in Ynysddu (Ynys-ddu), Caerphilly (Caerffili)

Approximate Location Map
Large Map »
Street or Overhead View
Contributor Photos »

If Google Street View is available, the image is from the best available vantage point looking, if possible, towards the location of the monument. Where it is not available, the satellite view is shown instead.


Latitude: 51.6204 / 51°37'13"N

Longitude: -3.2033 / 3°12'11"W

OS Eastings: 316792

OS Northings: 191971

OS Grid: ST167919

Mapcode National: GBR HX.90ZB

Mapcode Global: VH6DM.FJDN

Entry Name: Pen-y-Rhiw Round Cairn

Scheduled Date: 2 April 1956

Source: Cadw

Source ID: 2388

Cadw Legacy ID: MM149

Schedule Class: Religious, Ritual and Funerary

Category: Round cairn

Period: Prehistoric

County: Caerphilly (Caerffili)

Community: Ynysddu (Ynys-ddu)

Traditional County: Monmouthshire


The monument comprises the remains a burial cairn, probably dating to the Bronze Age (c. 2300 - 800 BC). The cairn is round in plan and measure 13m in diameter and 1m high and is turf covered. In the centre is a square hollow measuring 1.5m by 1.5m and 0.7m deep, within which are two upright slabs, the side slabs of a cist. The hollow contains a number of stones that probably originate from the body of the cairn. On the N side is a large hollow, measuring 2m in diameter and 0.5m deep and to the W of the cairn is an area of quarrying.

The monument is of national importance for its potential to enhance our knowledge of prehistoric burial and ritual practices. 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, together with environmental and structural evidence. Cairns may be part of a larger cluster of monuments and their importance can further enhanced 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

Other nearby scheduled monuments is an independent online resource and is not associated with any government department. All government data published here is used under licence. Please do not contact for any queries related to any individual ancient or schedued monument, planning permission related to scheduled monuments or the scheduling process itself. is a Good Stuff website.