Monument record 8552 - Deva Roman fortress

The current layout of the fortress at Chester is based in part on known archaeological evidence as well as studies of the expected design of Roman fortresses and in that respect Chester appears to follow standard practices with one or two unusual features. The first of which, most importantly is the size of fortress; Chester encompasses an area of 24.33 hectares (59.8 acres) in comparison to the next largest fortress in Britain at Inchtuthil (21.5 hectares). The reasons for this is not well understood, however. Dating for the fortress recovered from several lead ingots and an inscription from the Fortress Baths suggests a construction date of c79AD.

On its foundation, the typical Roman fortress was divided into three broad areas – the praetentura (front ward area), the latera praetorii (the central area) and the retentura (the rear ward area) which were then further divided into more functional areas known as insulae.

The praetentura at Chester appears to have around nine functional areas beginning with the first insula in the south east corner of the fortress where archaeological evidence has confirmed the presence of legionary quarters for a cohort (480 men) of the Roman army. Legionary quarters comprised six barrack buildings for the regular soldiers and six centurial houses for the officers.

The second insula fronting onto Bridge Street has been confirmed through archaeological evidence as the fortress bath complex. Bridge Street itself was the main road through the area, then known as the via praetoria on a north-south alignment leading to the via principalis (Watergate to Eastgate Street) on an east-west alignment across the centre of the fortress.

Insula 3 was located to the west of the via praetoria where archaeological investigation has only provided limited evidence and it is uncertain what its function could be. Finally insula 4 in the south west corner of the fortress may have contained another legionary quarters however again archaeological evidence is limited.

The area to the south of the via principalis comprises at least five insulae, two located to either side of the via praetoria, to the east two insulae (No’s 5 & 8) are tentatively believed to be tribune’s houses, however, archaeological evidence from these areas remains limited. To the west, the area between Watergate Street, Commonhall Street and Bridge Street contained a further two insulae (No 6 & 9) tentatively believed to be dedicated to the tribune’s houses. Finally in the far western corner adjacent to the via principalis insula 7 comprised the main granary stores for the fortress. This area was investigated in the 1950’s identifying the remains of three east-west aligned granaries.

North of the via principalis was the central area, largely given over to more monumental structures. Insula 10 on Eastgate Street comprised another set of cohort barracks confirmed through archaeological evidence. Adjacent to which, insula 11 may have contained the legionary commanders house, although here archaeological investigation has only provided glimpses of a well appointed building. At the centre of the fortress (insula 12), was the principia (Headquarters Building) used as the central administration building fronting onto Watergate Street and straddling what is now Northgate Street, its position highlighting its importance to the fortress. Archaeological investigation has indicated the building was substantial in size with a large hall to the rear and a monumental portico at the front. Next to this, insula 13 held the barracks of the First Cohort of the legion. Rather larger than the other legionary barracks, this area also contained a number of other buildings, however, despite large scale archaeological investigation the results remain confused and fragmented as a result of the rapid nature of the investigation and the limited publication of the results.

The area around the cathedral contained a possible four insulae (No’s 14, 15, 19 & 20), however, the opportunity for investigation is severely limited by the nature of the current land use. Immediately north of the principia archaeological evidence has identified a substantial courtyard structure in insula 16 some 160m in length believed to be a store building or possibly a hospital. The remaining part of the central area to the west of Northgate Street is divided into four insulae much of which has been subject to archaeological investigation.

Immediately to the north of Hamilton Place and the barrack of the First Cohort is an unusual structure occupying insula 17 unknown elsewhere in the Roman empire called the ‘elliptical’ building. This structure shows two distinct phases of construction; the late first century building was never finished in contrast to the later third century structure. The insula also held a small bath complex and a barrack type building tentatively interpreted as workshops. The ‘elliptical’ building itself is another unusual element of the fortress at Chester whose purpose is uncertain with currently no known parallels in the entire Roman empire.

Although the purpose of the elliptical building remains uncertain, the presence of a substantial monument at its centre would suggest some kind of devotional aspect. West of this building, insula 18 appears to have been given over to workshops. North of the elliptical building, insula 21 appears to have been given over to a series of buildings interpreted as stores and a large courtyard range tentatively interpreted as an exercise area for the cavalry. Finally in the central area, insula 22 appears to be another legionary barracks with substantial archaeological evidence for both the barrack blocks and the associated centurion’s houses.

The last area of the fortress, the rear ward section, was almost entirely given over to barracks for four cohorts, two each on either side of the via Decumana (insula 27 and 28). Archaeological investigations in this area have confirmed the presence of both barracks and centurial quarters relating to all four cohorts.

Between the barracks of the retentura and the central area was a series of four narrow insulae (No’s 23 & 24 to the east and No’s 25 & 26 to the west). Archaeological evidence has provided only limited evidence for these areas primarily limited to traces of a possible granary in insula 26 to the west of the fortress near Hunter Street.

<1> Carrington, P., 1977, The planning and date of the Roman legionary fortress at Chester (Article in Journal). SCH5913.

<2> Birley, Eric, 1948, The Status of Roman Chester (Article in Journal). SCH5764.

<3> Carrington, P., 1986, The Plan of the Legionary Fortress at Chester: Further Comparisons (Article in Journal). SCH5855.

<4> Carrington, P., 1986, The plan of the legionary fortress at Chester: a reconsideration (Article in Journal). SCH5940.

<5> Mason, D. J. P., 1986, The status of Roman Chester: a reply (Article in Journal). SCH5941.

<6> Taylor H., 1914, A Roman Centurion of the 20th Legion (Article in Journal). SCH5655.

<7> Haverfield, F, 1895, The Origins of Deva (Article in Journal). SCH5594.

<8> Haverfield, F, 1895, The Characteristics of Roman Chester (Article in Journal). SCH5603.

<9> Preston G. (Rev), 1887, The Roman streets of Chester (Article in Journal). SCH6747.