NGRef: SO2243
OSMap: LR148/161
Type: Vexillation Fort, Camp
NE (2.5) to Clifford (Worcestershire)
SW (17) to Y Gaer (Brecon Gaer, Powys)

The Roman Vexillation Fortress at Clyro

SO227435 c.1,300 x 860 ft
(c.396 x 262 m)
c.25½ acres
(c.10.4 ha)

The Clyro vexillation fortress is situated on the north-eastern flanks of a small hill just north of Haye on Wye in Herefordshire and immediately east of Clyro Castle, on the western bank of the River Wye in Powys, just a couple of hundred yards to the west of the river which here marks the border between England and Wales. In addition to the large campaign base there is a marching camp nearby at Clyro itself (SO2243), and a Roman fort lies four miles to the north-east at Clifford (SO2446).

"Clyro has been shown by Professor St Joseph to be a large well-defended site of 26 acres and a limited excavation in 1964 produced evidence of two periods. The earliest piece of samian has been dated to c.60." (Webster, p.85)

Clyro is possibly the scene of the near annihilation of Legio XX Valeria by the Silures tribe of South Wales, described by the Roman historian Tacitus:

"... A camp-prefect and some legionary cohorts, left behind to construct garrison-posts in Silurian territory, were attacked from all quarters; and, if relief had not quickly reached the invested troops from the neighbouring forts - they had been informed by messenger - they must have perished to the last man. As it was, the prefect fell, with eight centurions and the boldest members of the rank and file. ..." (Tacitus Annals XII.xxxviii)

The fortress measures 1,300 feet from north-east to south-west, by 860 feet transversely (c.396 x 262 m) within the ramparts, giving an internal occupation area of about 25½ acres (c.10.4 ha). The defences comprised of a substantial rampart and double-ditch system.

The Temporary Marching Camp

SO225430 1,200 x 900 ft
(366 x 274 m)
c.24¾ acres
(c.10 ha)
This camp occupies the summit of a hill overlooking a loop of the River Wye opposite Hay-on-Wye in Powys. The SE corner-angle and attached 800 ft (244m) lengths of the S and E sides were identified on aerial photographs taken in 1966. There is enough flat space on the top of the hill for a camp measuring about 900ft E-W by about 1,200ft N-S. The Clyro fortress lies on the NE slopes of this same hill.
See: Annales by Cornelius Tacitus, translated by J.Jackson (Loeb, Harvard, 1937);
Air Reconnaissance of Southern Britain by J.K. St. Joseph in J.R.S. xliii (1953) p.86;
Air Reconnaissance in Britain, 1955-7 by J.K. St. Joseph in J.R.S. xlviii (1958) p.95;
Air Reconnaissance in Britain, 1965-1968 by J.K. St. Joseph in J.R.S. lix (1969) p.123;
Rome Against Caratacus by Graham Webster (Batsford, London, 1993);
Roman Camps in England - The Field Archaeology by the R.C.H.M.E.;

Click here for a map of Clyro from

Page Citation: Kevan White (2018) "Roman Britain: CLYRO"