The Roman fort of Canovium (Caerhun) sat at an important ford on the Conwy river that connected the Roman center at Caernarfon (Segontium) with Chester (Deva). The following site has an extensive discussion of viritually every aspect of the Roman fort: http://www.betws31.freeserve.co.uk/Kanovium_Index/kanovium_index.html
“Situated on the west bank of the River Conwy, the Roman fort at Caerhun, known to the Romans as Kanovium or Conovium, is believed to have been established at this point to control a network of trackways already in existence at the time of the forts founding in the late 70’s A.D. Basically known as a ‘route blocker’ a fort situated at an area of strategic importance with the aim of restricting native movement. These tracks which ran N-S, and E-W had been dictated by the nature of the land which North Wales consisted of, basically the N-W area was a great upland massif, which consisted of the Carneddau, Glyderau, and Snowdonia mountain ranges, while the N-E area consisted of the Mynydd Hiraethog (Denbigh Moors) which ran north to end at a flat coastal plain. The people before the Romans desired easy routes into this area (and indeed Anglesey and the western seaboard) the route N-S entered North Wales near Llangollen, and used the Dee Valley to enter this broken landscape.
The E-W track connected the modern area of Deeside to Anglesey and the west, climbing up from sea level at modern Greenfield (near Basingwerk Abbey). The route today is slightly mirrored by the A55 road, however it veered away from the coast near St Asaph to eventually reach the Conwy river (above). From the river crossing it reached for the mountain pass of Bwlch y Ddeufaen, (pass of the two stones) to finally descend to Aber and once more be reunited with the coast (and now the A55). It would seem this track was considerably antique by the time of the arrival of Vespasian’s legionaries and auxiliary cohorts during 75-8 A.D, it was common practice for the army to utilize tracks already in existence especially in difficult terrain. While the Roman road was a strong factor in impressing the local folk and could be built as a large straight ‘agger’ even when the ground did not dictate such vast amounts of man hours to construct, however such ostentations were not considered appropriate in North Wales, and natural arteries already in use were transformed into something resembling the Roman road, though often were narrower than a Roman road in gentler countryside.” http://www.betws31.freeserve.co.uk/Bath-house/Caerhun_s_Dock/caerhun_s_dock.html
, and Gale in 1719 reported others, recently unearthed, bearing the legend
, which may have been broken. In 1801 Samuel Lysons uncovered a bath-house, 128 feet (39m) long, outside the north-east defences of the fort, along with tile-stamps marked
LEG XX VV
This fort is contemporary with the forts at Cicucium (Brecon Gaer/Y-Gaer) and Segontium (Caernarfon), being built around AD75. This is a square fort, each side measuring 410 feet within the ramparts, giving an occupation area of 3¾ acres. Defenses consisted of a 20 foot wide clay bank, fronted by two ditches. The gateways and internal buildings were of timber construction.
The size of the fort and the arrangement of its interior buildings suggest that Caerhun housed a Cohors Peditata Quingenaria, a regiment of foot-soldiers nominally five-hundred strong. The names of none of the garrison units stationed at Canovium are known.
“Additions in stone were made in the first quarter of the second century, and early rather than late in that period. The outer margin of the clay rampart was cut off to a width of 2 feet, and a stone wall 6 feet thick at its base built between the rampart and ditch. The inner ditch was filled up soon afterwards in order to strengthen the foundation of this wall. … The gateways also were rebuilt in stone. The east gate (porta praetoria) was a double opening with guard-rooms, singular in having its two arches of different widths (15 feet and 5 feet respectively). The new south gate was a double opening with no guard-rooms; but one of the arches seems to have been blocked up during construction for use as a guard-room. At the same time the internal buildings were all reconstructed in stone.” (Collingwood, p.37)
Excavation has revealed two timber periods in the early history of this fort, rebuilding being carried out sometime during Flavian times. The sacellum in the centre of the camp was the first building to be replaced in stone during the reign of Trajan, followed by the rampart-wall in Hadrian’s reign. Hadrianic and Antonine samian ware shows continued occupation through these times, but the well in the principia was filled around AD196/7, which may indicate either destruction or desertion at this time. Occupation at the fort was soon resumed, however, as attested by the building of a new cook-house behind the rampart around 235, and continued occupation throughout the third and fourth centuries is proven by pottery and coins dateable to both these periods. The last coin recovered from the site is one of Gratian (367-383).
After the fort was destroyed in c.AD200, the civilian settlement or vicus outside the defences was only sporadically occupied until the 4th century when it was finally abandoned. There were Roman copper mines at Pen-y-Gogarth (Great Orme’s Head), eight miles north of the settlement near Llandudno at the mouth of the River Conwy.” http://www.roman-britain.org/places/canovium.htm#rib2265