The Glamorgan-Gwent Archaeological Trust
Historic Environment Record
 

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Isca (Caerleon Roman Fortress)

Primary Reference Number (PRN) : 00514g
Trust : Glamorgan Gwent
Community : Caerleon
Unitary authority : Newport
NGR : ST33909060
Site Type (preferred type first) : Roman Fortress
Status : Scheduled Monument

Summary :
Overall number for legionary fortress of Caerleon , occupied late 1st-4th century. The fortress is situated on a glacial gravel terrace on the western side of the river Usk. It is one of the most important Roman military sites in Britain, being the permanent headquarters of the Second Augustan Legion, and the subject of extensive excavations from the beginning of the 20th century. Summaries of the history and archaeology of the fortress can be found in Boon 1972; Boon 1987 and Evans 2011.

Description :
The fortress at Caerleon lies on a river terrace at the confluence of the River Usk and Afon Lwyd, within the tidal reach of these rivers. The fortress measures c520m x 450m over the defences, enclosing approximately 2 hectares. It was built by the Second Augustan Legion in the 70s to replace the earlier fortress at Usk, and a series of rectangular timber buildings represented by beam slots, outside the western defences, have been identified as belonging to the construction camp. This area was subsequently developed for civilian occupation before being cleared and metalled, probably for use as a parade ground. Widespread signs of burning, dated to the end of the 1st century/beginning of the 2nd century, suggest that this remodelling may have been occasioned by a widespread fire in this part of the civil settlement (Boon 1972, 31-3).

The fortress measures c520m x c450mm over the defences, with an internal area of c20ha. The porta praetoria (sometimes referred to as the south gate) faces the south-east, where the road from Caerwent is presumed to cross the River Usk. Before publishing his landmark study of the fortress, Boon (1972) analysed the results from areas that had been excavated to produce a schema in which the fortress was divided into a regular scheme of 24 insulae. Subsequent work has produced only minor revisions to this plan, but since confirmation is lacking for significant areas, it must still be regarded as provisional. It remains however the best way of discussing the fortress layout and locating buildings within it.

It is generally accepted that construction of the fortress began c AD 70, with earth/turf and timber defences and timber internal buildings. Until the 1980s, the earliest known buildings were ones with cobbled foundations, but earthfast timber buildings of post-trench construction were subsequently identified in insulae X, XVII and XXIII (Zienkiewicz 1992a; 1993: Evans 1991; Evans and Metcalf 1992), and there seems no reason to suppose that they were not the norm over most of the fortress area, with the exception of reserved plots for major buildings such as the principia, the fortress baths and the basilica of insula XIX. This phase of activity is now below the water-table, making excavation difficult, and it is unsurprising that it would have been missed in the narrow trenches which were the normal means of investigation up to the last quarter of the 20th century. A few internal buildings, notably the baths, were constructed in stone from the first. It has been suggested, on the basis of a silver trulleus bearing the stamp ALA I TH found in the officer’s house in insula XI, that Ala I Thracorum was brigaded with Legio II Augusta during the earliest years of the fortress (Zienkiewicz 1993, 80-3), but in the absence of any other evidence this must remain no more than a conjecture.

The defences were rebuilt in stone at the beginning of the 2nd century. Some earth-fast timber buildings, such as Barracks B and C on the Roman Gates site, were replaced at the end of the 1st century with buildings represented by slight cobbled foundations, believed to have supported timber sill-beams. At others, the first replacement was definitely in masonry, with substantial cobbled foundations supporting walls of coursed rubblework. It is possible that in more utilitarian buildings, such walls did not rise to eaves height but may have been completed in mud brick or cob, given the large amounts of clay that was deposited during episodes of rebuilding.

There appears to have been very little activity during the second quarter of the 2nd century, when the legion was heavily involved on the northern frontier and the fortress at Caerleon was probably no more than a depot. There seems to have been renewed activity from the Antonine period onwards, and archaeological and epigraphic evidence indicates that internal buildings were being refurbished and replaced through the 3rd century(Boon 1972, 37-44, 53-9).

The exact nature of 4th century occupation within the fortress, whether military or civilian, remains to be established. Boon (1972, 62-9) maintained that military use of the fortress ceased at the end of the 3rd century, and that subsequent activity within the defences must relate to civilians moving in. It is however possible to interpret the same evidence as showing that military activity continued on a reduced scale in the 4th century after the army reforms carried out by Diocletian that resulted in a dramatic reduction in size of each legion, In this reading of the evidence, some buildings, such as the principia will have been decommissioned and demolished because they were too big for the new requirements. The careful dismantling of the principia suggests that there was a reason for clearing the site, or that the materials which made it up were required elsewhere. Pottery and coins dating to the 4th century have been found on the via principalis and in insula II (Myrtle Cottage), insula XIV (Golledge’s Field), insula XVII (Roman Gates and Vine Cottage) and insula XXIII (the Prysg Field), at least some of which relate to new building works (Boon 1972, 67, Evans and Metcalf, 31-3, 51-3). Unfortunately none of the new buildings are conclusively either military or civilian in form. Given the distribution of these blocks it is difficult to see where a new defensive perimeter could have been drawn to suit a smaller force, particularly since at almost all the points at which the ditch has been investigated it was filled with silt and rubble apparently fallen from the wall, indicating that the defences had been left standing until they collapsed (Nash-Williams 1931, 100; Davies 1959; Hawkes 1930, 151). Only on the Prysg Field was the ditch at the rear of the fortress carefully filled with clean clay (Nash-Williams 1931,101). However, the possibility remains that the whole fortress area remained in use during the 4th century largely cleared of buildings, as in the Saxon Shore forts.

Sources :
, 1935 , Newport
Boon G C , 1980 , Caerleon and the Gwent Levels in Early Historic Times
Boon, G C , 1972 , Isca: The Roman legionary fortress at Caerleon, Mon
Boon, G C , 1987 , The legionary fortress of Caerleon - Isca
Evans, D. and Metcalf, V , 1992 , Roman Gates Caerleon
Evans, E M , 2001 , Romano-British southeast Wales settlement survey: Final report ( © GGAT)
Evans, E M , 2010 , Caerleon
Evans, E. , 1991 , Excavtions at Sandygate, Cold Bath Road, Caerleon, Gwent , Britannia : 22 : 103-136
Hawkes, C , 1930 , The Roman legionary fortress at Caerleon in Monmouthshire: Report on the excavations carried out in the eastern corner , Archaeologia Cambrensis : 85 : 144-96
Nash-Williams , 1936 , Caerleon Excavations, 1936 , The Buletin of the Board of Celtic Studies : VIII pt.3 : 277-278
Nash-Williams V.E , 1923 , The Coins Found at Caerwent and Caerleon. , The Buletin of teh Board of Celtic Studies : II pt.I : 92-100
Nash-Williams V.E , 1927 , Caerleon , The Bulletin of the Board of Celtic Studies : 4 pt.1 : 94-96
Nash-Williams V.E , 1927 , Note on the Roman name of Caerleon. , Archaeologia Cambrensis : 82 : 378-379
Nash-Williams V.E , 1927 , The Caerleon Excavations , Archaeologia Cambrensis : 82 : 380-387
Nash-Williams V.E , 1929 , The Roman Legionary Fortress at Caerleon in Monmouthshire. , Archaeologia Cambrensis : 84 : 237-307
Nash-Williams V.E , 1936 , Caerleon Excavations 1936. , Archaeologia Cambrensis : 91 : 318-321
Nash-Williams V.E , 1936 , The Roman Fortress at Caerleon , Wales & Monmouthshire : 1 No.4 : 20-21
Nash-Williams V.E , 1937 , Caerleon Excavations , Archaeologia Cambrensis : 92 : 324
Nash-Williams V.E , 1937 , Caerleon Excavations, 1937 , The Buletin of the Board of Celtic Studies : IX pt.I : 90-91
Nash-Williams V.E , 1939 , White Hart Lane, Caerleon, 1938. , Archaeologia Cambrensis : 94 : 107-108
Nash-Williams V.E , 1939 , White Hart Lane, Caerleon, 1938. , The Buletin of the Board of Celtic Studies : IX pt.IV : 374-375
Nash-Williams V.E , 1951 , Note on the site of the Roman Legionary Fortress at Caerleon (Mon). , The Buletin of the Board of Celtic Studies : XIV pt.II : 176-177
Nash-Williams V.E , 1953 , Excavations at Caerwent and Caerleon. , The BUletin of the Board of Celtic Studies : XV pt.III : 231-242
Nash-Williams V.E and A.H , 1935 , Catalogue of the Roman Inscribed and Sculptured Stones Found at Caerwent, Mon. , Archaeologia Cambrensis : 90 : 314-315
Nash-Williams, V E , 1929 , The Caerleon excavations , Archaeologia Cambrensis : 84 : 140-5
Nash-Williams, V E , 1931 , The Roman legionary fortress at Caerleon in Monmouthshire: Report on the excavations carried out in the Prysg Field 1927-9. Part I , Archaeol Cambrensis : 86 : 99-157
Randall H.J , 1954 , The Roman Period. (A Hundred years of Welsh Archeology). , Archaeologia Cambrensis : 103 : 80-104
Richmond I.A & Crawford O.G.S , 1949 , The British Section of the Ravenna Cosmography , Archaeologia : 93 : 1-51
Robinson G.E. , 1877 , Roman Cardiff
Simpson G. , 1962 , Caerleon and the Roman forts in Wales in the Second Century AD. , Archaeologia Cambrensis : 111 : 103-166
Simpson G. , 1963 , Caerleon and the Roman Forts in Wales in the Second Century AD. , Archaeologia Cambrensis : 112 : 13-76
ST. Joseph J.K. , 1977 , Air Reconnaissance: Recent Results, 42 , Antiquity : 51 : 55-60
ST. Joseph J.K. , 1979 , Aerial Reconnaissance: Recent Results, 47 , Antiquity : 53 : 51-53
Strange J. , 1779 , An account of some remains of Roman and other antiquities in and near the town of Brecknock , Archaeologia : 1 : 294-307
Wheeler R.E.M. , 1929 , Caistor, and a Comment , Antiquity : III : 182-187
Wheeler R.E.M. , 1932 , Notes on Building-Construction in Roman Britain , The Journal of Roman Studies : XXII : 117-134
Wilson D.R. , 1969 , Roman Britain in 1968. I. Sites Explored , Journal of Roman Studies : 58 : 198-202
Wilson D.R. , 1970 , Roman Britain in 1969. I. Sites Explored , Brittania : 1 : 269
Woollett R.F. , 1885 , Caerleon, Monmouthshire , Archaeologia Cambrensis : 40 : 292-296
Zienkiewicz , 1993 , Excavations in the scamnum tribunorum at Caerleon: The legionary museum site 1983-5 , Britannia : 24 : 27-140
Zienkiewicz D. , 1983 , Early Christian & Medieval: Monmouthshire , Archaeology in Wales : 23 : 62
Zienkiewicz D. , 1983 , Roman: Monmouthshire , Archaeology in Wales : 23 : 43-45
Zienkiewicz, J D , 1986 , The legionary fortress baths at Caerleon
08/PM Desc Text//Boon GC/1962/Arch in Wales/p7 no30
03/PM Desc Text//Nash-Williams VE/1952/BBCS/V14 p176-7
01/PM Desc Text//Nash-Williams VE/Ro.Leg.Fortress Caerleon/p12-162
04/MM Record Card/OS//1957/ST 39 SW 1/
05/PM Desc Text/CBA/Boon GC/1969/Arch in Wales/
07/PM Desc Text/CBA/Boon GC/1967/Arch in Wales/
10/PM Desc Text/NMW//1980/Al An Sorrell, Early Wales Recreated/No4 6
06/PM Desc Text/CBA/Boon GC/1968/Arch in Wales/
09/MM AP/GGAT/Parkhouse JP/10.02.86//
02/PM Desc Text//Nash-Williams VE/1954/Ro Frontier in Wales/p18-21

Events :
E001050 : Roman Gates, Caerleon (year : 1980-1)
E003743 : Proposed Usk Barrage Initial Archaeological Assessment (year : 1991)
E003871 : The White Hart Inn, Caerleon, An Archaeological Evaluation (year : 1998)
E001411 : The Roman fortress of Caerleon and its environs: A framework for research (year : 2004)
E002452 : Caerleon Rugby Pitch WB (year : 1999)
E002584 : Broadway, Caerleon EVAL (year : 2000)
E001657 : Romano-British Southeast Wales Settlement Survey (year : 1998-2001)
E007502 : 19 Goldcroft Common, Caerleon (year : 2018)
E007570 : Caerleon House Nursing Home, Goldcroft Common, Caerleon, Newport (year : 2021)

Related records
GGAT Historic Environment Record (HER) 16144g

Compiled date : 02-02-1988


March 29, 2025, 4:24 am - HTML file produced from GGAT HER Charitable Trust Ltd. Heathfield House, Heathfield, Swansea SA1 Tel. 01792 655208; Fax 01792 474469 website: www.ggat.org.uk  email: her@ggat.org.uk Registered Charity no. 505609
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