In case you missed it on the social media channels, our year got off to a fantastic start when the team appeared on Digging for Britain (series 9, episode 3)!
Digging for Britain’s Roman lead workings
The show gave us a glimpse of industrial practices associated with processing Gallena, Lead Ore, at our Navio Roman fort and vicus site near the village of Brough, in the heart of the Hope Valley in the Peak District. The Peak District of Derbyshire is an area rich in mineral wealth, specifically lead, which was a major driver for the Roman presence at Hope. At Navio geochemical survey undertaken by ARS Ltd has revealed the concentrated chemical traces of lead on site, presumably occurring as a by-product of ore processing (although we don’t have any direct evidence for smelting or casting on site). Lead was a vital commodity in the Roman world and was used in making everything from fine jugs, bowls and cups to waterproofing for rooves and pressurised waterpipes to feed fountains and baths across the Empire.
The history and archaeology of Navio Roman Fort
Previous excavations suggest the fort itself was originally established in timber around AD79, replaced in stone in the second century, and continued in use and occupation until the mid-fourth century. The strategic importance of the site is that for the Romans it allowed control of access across the southern Pennines, between other military installations that created a fortified east-west corridor across central Britain, in addition to allowing for control and protection of lead supply and perhaps other minerals coming out of this part of Derbyshire.
The Roman fort was designated a Scheduled Ancient Monument in 1925 and there have been several phases of archaeological investigation here in the decades since, each revealing a little more about the site. These include the large gritstone slabs of the ‘strong room’ (which are still visible above ground even today), as well as the cobbled yard areas and the road network into the south-east of the fort.
One of the major findings early on in the 2019 excavation was a large ditch and bank which defined the northern limits of the vicus (settlement outside the fort). When paired with the surrounding landscape features (which were identified in previous archaeological work and on Lidar imagery) it became clear that at one point the western part of the Roman vicus settlement would have been enclosed effectively on all sides, effectively becoming an annexe, or extension of the fortified area, for the fort itself.
The Cobb Wall
The ARS Ltd excavations have also established a surprising level of preservation at the site, amply demonstrated by the presence of upstanding sections of an earth or ‘cobb wall’. This wall was associated with a boundary around a timber and stone building to the north with an open area, probably part of a yard, to the south. A cobb wall is made of earth or clay laid in lifts on a stone foundation. Other examples of earthern architecture such as this, dating to the Roman period, are rare outside urban settlements, with other examples identified at Colchester and in London. Finding a surviving example of this in the Peak District was unusual and exciting, and led us eagerly into subsequent excavations in 2020 where we discovered it was quite extensive, standing to a height of 20cm—remarkable considering the ploughing that had happened on site.
Archaeological artefacts of the Hope Valley
We’ve uncovered many artefacts at the site to date. These finds include pieces associated with food storage and preparation, to table wares from both mainland Europe and closer to home.
For example, we’ve found:
- a rim of amphora, produced in Spain, and most likely used for the transportation of garum (a fish sauce) popular with the Romans;
- Samian ware/Terra Sigillata pottery from France and dating to the mid-second century AD;
- a dish with lattice work from the south of England;
- Roman Gaming counters;
- and some glass objects too, which indicates the relatively high status of the occupants here.
If you’ve been seeing our #FindsFriday posts on our social media channels, you’ll also have seen the ballista balls recovered from the excavations at Navio. These were weapons fired by the Roman crossbow-shaped catapult. Ours were discovered to be made of local stone and indicate that the vicus was defended, with perhaps manufacture of the balls taking place there.
Part of the global Roman economy
With these artefacts, and the lead working, the site continues to play an important role in shedding light on the Roman occupation of Britain and along the area of the ‘lost frontier’ that had been the limit of the Roman empire prior to the Hadrianic and Antonine frontiers further north.
And while the industrialisation and the siting of a Roman fort seems remarkable considering the rural setting within the Hope Valley, the finds recovered so far do indicate that it was very much part of the Roman global economy. The military presence would certainly have been responsible for the exotic goods on site from further afield.
ARS Ltd has now been working at Navio for the last three years for Breedon Ltd who operate the adjoining shale quarry. With the fort itself protected from the quarry workings by a screen of trees, each time the quarry is extended within its permitted boundaries we as archaeologists appreciate the chance to extend knowledge of the site, share it with the public and have local volunteers participating in the excavations. Breedon has been a great steward of the vicus site and it has been a pleasure working with them to record the archaeology and make it available to the public. Watch out for the full site report that will be made available online in the coming year!
To see us on Digging for Britain, where you can also get more of an insight into how the lead was worked, check out series 9, episode 3 of the show on BBC iPlayer >