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Old Mills Moat

In the community of Trewern.
In the historic county of Montgomeryshire.
Modern authority of Powys.
Preserved county of Powys.

OS Map Grid Reference: SJ27751289
Latitude 52.70871° Longitude -3.07067°

Old Mills Moat has been described as a Timber Castle although is doubtful that it was such, and also as a probable Fortified Manor House.

There are earthwork remains.


Old Mills Moat (SJ 277 129), though previously regarded as a medieval moated site, is unusual. It occupies sloping ground between the foot of the Breidden Hills and the R. Severn, and consists of a strong quadrangular enclosure of 0.40 ha (0.99 acres), with a larger annexe of 0.85ha (2.1 acres) on more level ground to the W., extending to within 32 m of the Severn. The smaller enclosure is defended on its upper E. side by a wide irregular bank, fronted by a massive wet ditch, 8 m wide. Here, the ground outside rises so steeply that the counterscarp of the ditch is up to 2 m higher than the top of the internal bank, but its steep scarp and the wet moat constitute a formidable obstacle. A rill feeds the ditch and flows along the N. flank, skirting a more modest bank. To the S., the strong upper E. bank and ditch turn to make a well-formed acute angle, but they continue to the W. for only 22 m, beyond which a marshy hollow defines this flank. A scarp and modest wet ditch mark the W. side facing the annexe. The interior, which measures 80 m N-S. and 40 m to 60 m E-W, is very irregular, but no certain traces of buildings are apparent. The annexe is subdivided by hedges and is much ploughed down, surviving only as a low bank outlining its W. half and no longer visibly connected to the upper enclosure. Until the 19th century, the ancient Gorther Ford crossed the Severn immediately beyond the annexe. The significance of this ford, on the W. boundary of Mercian territory (and the diocese ofHereford) in a long gap in Offa's Dyke, is discussed by Noble. (Spurgeon, 1988)

A subrectangular enclosure, c.84m N-S by 53m, banked, except to the W, and moated. A further, dependent enclosure, c.110m W-E by 80m, on the W is visible now only as a cropmark (Cpat Prn38186). (Coflein)

Moated enclosure. 57m E-W, 85m N-S. Possible earthwork outworks to the south. Ditch 1.4m deep, interior raised 0.6m above ditch floor. Faint trace of possible building platforms. Possible annexe to west. There is a possibility that this site is related in some way to Offa's Dyke. It could be some form of Mercian camp connected either with its construction or its subsequent control. It is very unlike any normal local moated site. Note medieval ford of river Severn adjacent (CHRM). (Clwyd Powys Archaeological Trust HER)
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This record last updated before 1 February 2016