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Tomen y Mur

A Scheduled Monument in Maentwrog, Gwynedd

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Latitude: 52.9285 / 52°55'42"N

Longitude: -3.9222 / 3°55'19"W

OS Eastings: 270886

OS Northings: 338521

OS Grid: SH708385

Mapcode National: GBR 5Z.MFQT

Mapcode Global: WH55P.QNG8

Entry Name: Tomen y Mur

Scheduled Date:

Source: Cadw

Source ID: 274

Cadw Legacy ID: ME078

Schedule Class: Defence

Category: Fort

Period: Roman

County: Gwynedd

Community: Maentwrog

Traditional County: Merionethshire


A large scheduled area in two parts containing some ten sites. Adjacent and intervening areas are also scheduled. The principal sites are the Roman fort with its vicus and the Roman parade ground and amphitheatre. Within the fort is a Norman motte and probable traces of a bailey.

The following areas/sites have been allocated numbers, and will be described individually.

i Roman fort SH70603865 ii Vicus and bath-house SE of fort SH70703855 iii Sites NW of fort SH70603880 iv Parade ground E of fort SH70803875 v Amphitheatre NNE of fort SH70813890 vi Tribunal/barrow ESE of fort SH70903865 vii Enclosures S of vi SH70853865 viii Leat serving bath-house, running S of parade ground

ix Roman roads and bridge abutment SE of fort SH70723851 x Medieval motte SH70553868

Other sites within the area of Me078 are the three sets of Roman barrows SE of the fort, the two Roman barrows NE of the amphitheatre and the field bank SE of the fort.

There are a number of sites outside the scheduled area which appear to be of Roman date. At SH71013885 is a horseshoe-shaped bank with an opening to the E, described as a possible emplacement for a training catapult.

At SH71273817 are the remains of a square earthwork, thought to have been a Roman practice camp.

At SH71643838 is another practice camp with clavicular entrances.

Archaeological Item # ME078A Description of the fort taken from various published sources:

The fort shows evidence for at least two periods, involving a reduction in size. The first encampment appears to have been a rectangle with rounded corners enclosed by an inner bank, a ditch, and an outer bank, with overall measurements of about 700 ft by 520 ft and an interior of 500 ft by 360 ft. The presence of an outer bank, which is clearly visible around the W corner, is not in accordance with normal practice in the construction of auxiliary forts. The rectangle has its longer axis downhill from NW to SE, with the highest rampart placed just on the crest of the hill. This was the side omitted from the rebuilding, and the foundations of the original gateway, probably the prota decumana, may well survive at a point indicated by a break in the bank.

There is no surface indication that this earth and timber fort was reconstructed with stone before the reduction in size took place. This reduction was carried out by setting back the defences on the NW side by about 100 ft, giving a new internal area of 400 ft by 360 ft. The smaller fort was walled with stone, possibly at the same time as the reduction took place, but of this wall hardly anything remains visibly in position, although quantities of squared stones taken from it can be seen built up as field walls around the site. The stone used by the Roman builders was the local Cambrian grit; this could have been quarried at several places below and to the SW of the fort, which itself stands on glacial drift overlying slates and shales.

The defences of this period now appear as banks surmounted by the modern field walls, and the interior of the fort, which has long been cultivated, is level with ther tops [the top of the banks]. The motte is built astride the centre of the NW side of the reduced fort, and may well cover and preserve the gate that must have existed at that point. The other three gates have been largely destroyed, but their positions can be made out, and at the SE gate remains of rectangular guard chambers remained visible until quite recently. Ploughing inside the fort has levelled most of the area; a slight bank on the NE of the motte may be the remains of an inner bailey associated with that structure, but irregularities in the ground to the SE of it possibly indicate the site of the Praetorium.

The two main structural phases, already indicated by surface features, were examined by excavation in 1962. The first, presumably Flavian, fort had defences of earth on a turf foundation, surmounted by a timber palisade; it was unusual in possessing a counterscarp bank outside the NW defences. The only modification detected was that the two original ditches were rapidly replaced by a single, larger ditch cut into the berm immediately in front of the rampart.

The reduced fort consisted of the Praetentura and principal buildings of the original fort; the whole Retentura was abandoned and its NW rampart slighted. The new NW defences overlay the via quintana of the first fort. From the first, the new fort appears to have had a stone wall; in the new NW defences this lay in front of a rampart of turf. The slight eveidence for dating of the reduced fort suggests that it should be assigned to the aerly years of Hadrian. There is at present no evidence to suggest that military occupation of Tomen y Mur continued beyond 140.

Measured by the OS, the fort was 158 m NW-SE by 110 m transversely. The inner bank on the E side was 4 m wide and 0.3 m high. The fort itself was from 1.6 m high on the NE side to 3.5 m high on the SW side, above the ditch, which was, where best preseved on the NW side, 11 m wide and 0.3 m deep. The outer bank was only visible on the W corner and the SE side, where it was 10 m wide and 0.3 m high. The original entrance on the NE was noted but 'no trace remained' of other entrances. The reduction in the area of the fort is marked by a ditch 30 m SE of the NW side, which measured 9 m wide by 0.3 m deep.

Archaeological Item # ME078B Description from various published sources: The land sloping down from the SE wall of the fort to the stream has, in part, escaped agricultural clearance. Here, on the most sheltered part of the whole site, are the remains of various buildings. These are either side of the roadway, which runs from the SE gate in an almost straight line, not on the axis of the fort but turned about 15 degrees S from it.

In the field adjoining the SE side of the fort, S of the gateway, is a levelled area with the remains of low banks forming a rectangle, presumably the site of a building or buildings. The field N of the gateway has been cleared, and is crossed by modern drainage ditches.

The second field, SE of the fort, contains the foundations of a number of rectangular buildings, which flank and delimit the roadway. The ground has been partly levelled over this area. The surface indications now consist of grass-grown banks 2 or 3 ft wide, and on average 1 ft high; some of these to the S of the road have been the site of various diggings, which have revealed the lowest courses of stone walls, retaining in places their original plastering.

Excavations were first carried out at this point before the 1850 visit of the CAA, when bones, bricks, tiles and charcoal were the objects found. There were further explorations before the visit of 1868, and these added pottery 'of a dark, coarse character' to the list of finds. The site of the excavations was the bath-house, and some of the other remains appear to indicate the presence of a civilian settlement. A suggestion is made on the OS NAR cards that the settlement is post-Roman.

Andy Davidson's visit text: To the SE of the fort, on either side of the Roman road, are the remains of a vicus and bath-house. The bath-house lay on the [S]W side of the road, but the remains have been badly disturbed by the 19th C excavations, and the plan is further obscured by dense blackthorn scrub. However, a T-shaped wall junction is still visible. Possible Roman masonry is visible at the NW corner of the site, underlying the modern field wall.

NW of the bath-house is the levelled area mentioned by Gresham, now covered in rushes, and between that and the fort a series of three terraces.

On the other side of the road from the bath-house is a series of three or four small rectangular enclosures, with a longer rectangular enclosure to the S, running alongside the road. Wall facings are visible amongst the banks dividing the enclosures.

Archaeological Item # ME078C The motte is about 10 m high and is surrounded by a ditch 4 m wide, with a counterscarp bank surmounted by a modern field wall. The top is uneven, with two principal hollows on SE and SW which may represent the sites of original buildings (or possibly robbing). It is slightly oval, measuring approx. 14 m N-S by 19 m E-W.

Archaeological Item # ME078D Two low, grassy mounds with a later bank running between them. The northern mound is c. 1.5 m square and 0.2 m high surrounded by a shallow ditch and counterscarp bank, 6 m across altogether. The S mound is 0.5 - 0.7 m high but otherwise similar. The bank is low and grassy, 1.5 m wide and 0.2 m high.

Archaeological Item # ME078E The amphitheatre consists of a circular bank of over 30 m diameter, of grassed-over stone. It is 1.5 m - 2 m high and c. 2 m wide.

Archaeological Item # ME078F The SE bank is the most prominent feature of the unfinished parade ground. It is 0.7 m high and 3 - 4 m wide. The interior is clearly levelled.

There is a leat crossing the field on a bearing of 234 degrees, to the bath-house. It is 1 m wide and 0.2 - 0.3 m deep.

S of the parade ground Jarrett's plan shows a series of enclosures, and a regular mound to the SE (the 'tribunal'). These are visible but are nothing like as clear and regular as shown on this plan. The mound is between 2 m and 3 m high and is probably an enhanced natural feature.

Archaeological Item # ME078G The road which leaves the SE side of the fort crossed the stream to the SE of the site by a bridge, which has now gone, but the abutment on the lower bank remains visible. The continuation of the road to the SE appears to be visible for some distance (E of the line of pylons), but a more likely position for it would be on the crest of the hill slightly to the W.

Archaeological Item # ME078H A horseshoe-shaped bank with opening to the E, described as a possible emplacement for a training catapult.

Archaeological Item # ME078I At SH71273817 are the remains of a square earthwork, thought to have been a Roman practice camp. At SH71643838 is another practice camp with clavicular entrances.

The monument is of national importance for its potential to enhance our knowledge of Roman settlement practices. It is an important relic of the Roman landscape and retains significant archaeological potential. There is a strong probability of the presence of environmental and structural evidence, including preserved internal and external floor levels.

Source: Cadw

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