Tomen Las Castle Mound, Pennal

Has been described as a Certain Timber Castle (Motte), and also as a Certain Palace (Other)

There are earthwork remains

NameTomen Las Castle Mound, Pennal
Alternative NamesY Domen Las; Towyn
Historic CountryMerioneth
Modern AuthorityGwynedd
1974 AuthorityGwynedd

Tomen Las is a medieval castle represented by a mound or motte, that would originally have been crowned by a great timber framed tower. The castle is undocumented, however, it was probably attached to the court or llys of the Princes of Gwenydd at Pennal, removed from the earlier site in the Roman fort on Cefn Gaer (see NPRN 300159). A princely hall and associated offices would have stood near the mound, although the site is generally marshy. The surviving remains include a circular mound 26m in diameter that rises 3.0m from the traces of its ditch. The level summit is 15-17m across. There are no traces of further earthworks. The mound was treated as a tree clump in Plas Talgarth park (see NPRN 265177). (Coflein– John Wiles, RCAHMW, 11 February 2008)

Tomen Las Castle Mound is located in Talgarth Park, in marshy ground alongside a stream in the valley bottom of the Afon Pennal. The monument comprises the remains of a motte and the faint remains of a ditch, dating to the medieval period (c. 1066 -1540 AD). A motte is a large conical or pyramidal mound of soil and/or stone, usually surrounded by either a wet or dry ditch, and surmounted by a tower constructed of timber or stone. The surviving remains of Tomen Las measure approximately 4m in height and 30m in diameter, with a flat top approximately 15m across. (Scheduling Report)

This site is a scheduled monument protected by law

Not Listed

The National Monument Record (Coflein) number(s)
County Historic Environment Record
OS Map Grid ReferenceSH697002
HyperLink HyperLink HyperLink

No photos available. If you can provide pictures please contact Castlefacts

Most of the sites or buildings recorded in this web site are NOT open to the public and permission to visit a site must always be sought from the landowner or tenant.

Calculate Print


  • Morgan, Gerald, 2008, Castles in Wales: A Handbook (Talybont: Y Lolfa Cyf.) p. 242 (listed)
  • King, D.J.C. with Kenyon, J.R., 2001, 'The Castles: a Study in Military Architecture' in Smith J.B. and Smith L.B. (eds), History of Merioneth Vol. 2 p. 412
  • Pettifer, Adrian, 2000, Welsh Castles, A Guide by Counties (Boydell Press) p. 120
  • Salter, Mike, 1997, The Castles of North Wales (Malvern) p. 49 (slight)
  • King, D.J.C., 1983, Castellarium Anglicanum (London: Kraus) Vol. 1 p. 277
  • RCAHMW, 1921, An inventory of the Ancient Monuments of Merionethshire (HMSO) p. 168 no. 534 online copy


  • Hogg, A.H.A. and King, D.J.C., 1963, 'Early castles in Wales and the Marches: a preliminary list' Archaeologia Cambrensis Vol. 112 p. 77-124