So, a résumé of the appearance of the name/word ‘Traiectus’ in the Antonine Itinerary:
1. Examples where traiectus simply refers to a crossing – the crossing of the Adriatic, the crossing of the Strait of Messina, the crossing from N. Africa to Sicily. Whether or not Traiectus was, in a few cases, also the name given to a particular place (for example, near Reggio di Calabria and the Strait of Messina (Parthey §86 & §98)? – unattested, apart from in the Itinerary itself), it can be said that in these cases the crossing itself was by boat over a substantial body of water (even the Strait of Messina is over 3km wide at its narrowest point). Could that possibly be what the Traiectus between Caerwent and Bath was – not a particular settlement but just ‘the place to cross’ something (river, strait, sea)?
2. ‘Traiectus’ in Aquitania, between Agen and Périgueux: the certainty is that the crossing concerned was over the river Dordogne, close to present-day Lalinde. [A diversion was whether or not Lalinde was the Diolindum of the Tabula Peutingeriana. For what it’s worth, intriguing though the similarity of Lalinde and Diolindum is, I would guess not. For one thing, Peutinger’s distances for Diolindum are a more accurate fit for the road to Cahors than the Itinerary‘s road to Périgueux.] This does leave ‘Traiectus’ as a possible place name, perhaps for modern Lalinde or Pontours. It is the only other possible place name (besides the Gloucestershire example) which appears in the subject form ‘Traiectus’ rather than ‘Traiecto’ or Traiectum’.
3. Utrecht as a place name derived from something like ‘Ultra Traiectus’: Is this the only example where a modern (and historically attested) name is clearly derived from Roman Latin (i.e. not medieval) traiectus? The crossing here referred to is of the river Rhine. The name is attested in Itinerary §369: Traiecto is 17 Roman miles south of Albinianis (Alphen aan den Rijn) and 15 Roman miles north of Mannaritio (Maurik). As for Maastricht, there is no evidence of the name Traiectum ad Mosam or Traiectum Mosae in Roman times: it is not mentioned in the Itinerary. Modern ‘Maastricht’ seems to be derived from its medieval name of Mosae Traiectum. Somewhat similarly, Traiectum Rhodani was a late description of the town of Beaucaire. It is a crossing place over the river Rhône on the Via Domitia, but the Roman name for Beaucaire was apparently Ugernum; so Traiectum Rhodani seems to be a description rather than a place name: ‘the traiectum Rhodani was at Ugernum’.
Does all this cast any light at all on the ‘Traiectus’ between Bristol and Bath? It certainly suggests that the traiectus would be over a wider body of water than the Boyd at Bitton. Even the Avon is a stream compared with the Dordogne which, at its narrowest, is nearly three times wider (150m) than the Avon at its widest at this point. The Rhône at Beaucaire is at least 200m (the Île du Comté divides the river in two at this point, otherwise the crossing to Tarascon would be 400m wide). The Meuse at Maastricht is 150m wide. The Rhine at Utrecht is over 100m wide. [But see the comments below on the Avon floodplain].
Neither of the two competing identifications for the Gloucestershire Traiectus is new. There is the ‘corrupt manuscript’ theory which would have the traiectus as being across the Severn estuary. That would answer the puzzle as to why the Itinerary makes no mention of a crossing from (modern) Wales to (modern) England. Such a ‘traiectus’ would be similar to other examples in the Itinerary – just ‘a crossing’ rather than a station. The theory could merit closer investigation to see if this amount of corruption could be plausibly explained.
The second possibility is that the crossing was over the river Avon. But if the Antonine iter Sea Mills > Traiectus > Bath was following the known Roman road north of the river, there would be no need to cross the river at all; nor has a Roman settlement of any importance been found here north of the river. Nevertheless, and there’s nothing new here, any crossing place for a north-south road down to the Mendips looks most likely to have been at Keynsham [NB in Somerset, not Gloucestershire – Ed]: there are at least three areas where Roman remains have been found: i. Durley Hill to the west where the so-called ‘palace’ was discovered ii. beneath the Somerdale factory, and possibly iii. further east close to Wellsway school. Whatever the purpose of the ‘palace’, it was a large enough building to be part of extensive Roman activity in the area. The Somerdale site lays claim to being a small town and already is Traiectus in some sources. It even boasts a Trajectus Way (as well as roads named after Hadrian, Claudius, Augustus, Titus and Tiberius).
Preparatory investigation prior to development in East Keynsham drew a claim that traces of a north-south road on the site east of Wellsway school had been identified. On the developers’ plans the direction of the road points towards Bitton where, it should be said, there are few Roman remains to excite interest.
But the puzzle here is why does the Itinerary‘s journey [i.e. Abone mpm xiiii, Traiectus mpm viiii, Aquae Solis mpm vi] mark Traiectus, given that the known Roman road, marked on the OS maps between Hanham and Oldland, and between Bitton and Swineford, doesn’t cross the Avon? Was there a mansio at Traiectus/Keynsham where travellers could stay by making a small detour over the river? How likely is that, with a mere 6 Roman miles either to or from the more important town of Aquae Sulis?
One further thought: the Roman road is a little distance from the river nowadays, but was it in Roman times? Was part of the Avon’s flood plain permanently below water? Interesting thought, but the river level would seem to have been at an impossibly high level for that to be the case. But, if it was (yes, highly unlikely, though the area might have been marshy), the road would have run just alongside the river bank; and Willsbridge [vii mpm from Aquae Solis] would have been the closest crossing point to the extensive settlement known to exist underneath the Somerdale site on Keynsham Hams – which would likewise have been near the marsh or water’s edge; as would the Durley Hill ‘palace’. So, for fun:
In fact, maps of the possible sea/river levels suggest that the area south of the river would have been first to flood, especially Keynsham Hams (though not the eastern side where Somerdale was built, nor the Durley Hill ‘palace’ site). It would need seemingly impossibly high levels before the northern floodplain was covered completely. So, Not This Way. But it leaves the possibility that there was a pause at Willsbridge and a quick traiectus across the river to the Keynsham Hams settlement (Somerdale) for a bit of refreshment ….
Next time: a short look at the suggestions regarding the crossing of the Severn estuary, published in the Victorian County History, Somerset vol I, Romano-British Somerset Part 3, ‘THE ROAD FROM BATH WESTWARDS TO THE SEVERN CROSSING AND SOUTH WALES’.