Looking at the geography of Somerset at the point where the three (perhaps four) Celtic tribal groupings would have met, it turns out that there is no shortage of watery places. But a main ‘civitas’ πόλις would have signs of British and Roman occupation of some description – presumably – because the Romans wouldn’t simply have designated an undeveloped Iron Age hillfort and expected that to be some sort of administrative centre. Their own custom was to build their cities close to where the tribal centres had been.
The blue rectangle is roughly, give or take, where No Man’s Land was. The southern line is just below the mouth of the Parrett (the supposed limit of the territory of the Dumnonii) and passes just north of Ilchester, in Durotrigan territory. To the north, the boundary lies just north of the Axe – one estimated boundary of the Dobunni – and passes eastwards over the Mendips.
It’s a fascinating area: Brean Down, with its Romano-British temple and possibly a small port; Charterhouse Roman Town, a centre of Iron Age and Roman lead mining; the small Roman port of Rackley on the Axe and, a little further along, Cheddar where there may also have been a port; just north of the Poldens, the two Iron Age lake villages of Meare and Glastonbury; the Roman ports at Combwich and Crandon Bridge on the Parrett; and Ilchester itself, traditionally identified with Iscalis, at the centre of a network of Roman roads – the Fosseway going north and south, the road to Dorchester and a smaller road along the Poldens, perhaps to Crandon Bridge.
Another suggested site lies to the north of the Mendips: Gatcombe, in Long Ashton. There was a Roman settlement here of unknown extent, of which Professor Cunliffe says:
“If it were a settlement of any size it would be tempting to equate it with the place called Iscalis by Ptolemy, which according to him lay to the west of Aquae Calidae (Bath). To suppose that Iscalis was Gatcombe would be as reasonable as any of the other situations proposed for it …” (‘Excavations at Gatcombe, Somerset, in 1965 and 1966’, Proceedings, University of Bristol Spelæological Society, 11-2 pp 126-160).
I’m not sure it’s ‘as reasonable’ as any of the others: Professor Cunliffe estimated the Dobunni were settled as far south as the River Axe, and Gatcombe would therefore have been in their territory, not that of the Belgae. But, if there was such a place as Iscalis – not 100% certain, it’s hard to see a place in any of the known tribal territories that would fit it.
According to Ptolemy in the 2nd century, the Dumnonii had four πόλεις – Voliba, Uxella, Tamara and Isca Dumnoniorum; the Durotriges had one – Dunium, though Durnovaria and Lendeniae also had some significance at some point. For the Dobunni, only Corinium was named, though there is speculation that they had a more southerly division. And the Belgae: the term seems to be used for a later wave of migrants from various tribes, but it’s unlikely that they would have established themselves so far west by the 2nd century, when Ptolemy was writing.
What would I guess? Well. Of course. Iscalis was … Burnham-on-Sea :-).
More follows …