A Line Along the Taw

The Taw is a North Devon river that runs from the center of Dartmoor down east of Okehampton and then winds its way north up to Barnstaple where it enters an estuary that is also attached to the Okement River. Both rivers start their course from a boggy morasse in the center of Dartmoor that's easier to call Cranmer Pool than anything else. In fact, there's less than a half a mile between the two river 'heads' and, within the space of perhaps two square miles, you can find the sources of four principle rivers, the others being the East Dart and the Teign.
But that's mostly incidental; the Taw is of concern because it positions a Roman fort and also - because this isn't just interesting, but might be related - it traces a collection of Grove-related placenames that certainly have a Brittonic (Celtic for those who have a preference) root, but are also composed of Germanic elements with the same meaning. The British element is Nymet, incorporating the Latinised Nemeton, and the Germanic element is Beer, Bear or Beere.
The fort in question is sited just south of North Tawton along the line of the Roman road from Exeter - at that point now the A3072, which spurs off the current A377 but was, at the time, the same road. Other forts are at Bury Barton and Okehampton. The North Tawton fort is actually one of perhaps two or three that, at different times, evidently defended a good crossing point of the Taw.
Current thinking has it that the forts date to the immediate post-conquest phase of Roman Britain - immediate meaning a few decade after - at a time when the 2nd Legion under Vespasian was consolidating its hold on the south west peninsular, in the process subduing the Dumnonii tribe. However, if that was exclusively the case, then the forts would have probably existed for just a finite time. That the Roman Road survives and that it crosses the Taw at pretty much the same point as it did two thousand years ago, makes a good case that the forts were in existence longer and that they, or what they generated in the local surrounds, was still active well after Britain was removed from the Empire.
So, because I'm a boring bugger who's got an interest in all of this, I'm establishing a project of sorts to visit the forts, hopefully trace the Nymet-related places and generally make a nuisance of myself for a time. Most likely I'll do this on my own - I don't doubt that even Gloria, the invented Witch of Sheepstor, would be bored rigid by such a venture ...