An interesting snippet from a review of Ordelle G. Hill’s now-unobtainable Looking Westward: Poetry, Landscape, and Politics in Sir Gawain (2009).
Apparently in tracing Gawain’s journey, Hill had Gawain reaching Blackshaw Moor near the North Staffordshire town of Leek. In my own book on the topic Strange Country I also get Gawain to the vicinity of the same Moor, but… then I have him following the ‘Earlsway’. Thus Gawain hooks south along a long ridgeway path and is then headed straight for Alton Castle, which matches the poet’s description very well indeed — and yet curiously no other scholar seems even to have noticed this castle.
Instead, Hill’s book has Gawain heading north from Blackshaw Moor, toward the town of Buxton and away from the dialect area. Hill then identifies “the Green Chapel with Deepdale Cave near Buxton”, according to the review I read. The cave is also known in the local antiquarian literature as the ‘Thirst Hole’.
Deepdale Cave looks physically very unlikely to me, though, judging by postcard images of the cave. More like an aircraft-hangar entrance, though I guess it may be been enlarged since the 1370s?
Still, Hill offers a closer suggestion than a recent unsupported claim from another author that Gawain’s journey has him journeying ultimately “into southern Yorkshire”, or the unsupportable notion among dogged Cheshire/Stanley advocates that he must have remained in the Wirral.
Incidentally, there’s another snippet of evidence that Gawain’s likely route had dramatic rock formations…
“Blackshaw Moor, where you are greeted by a dramatic panorama of intimidating rock formations. They rise up suddenly, looking like a row of ancient fortresses.” (Staffordshire Folk Tales, 2011)

