I had forgotten about this broch till I just this moment came across the prints. To paraphrase it's one of the ruins that Petrie buggered about a bit. It stands quite well behind Hoxa but this wall is his reconstruction. Would have been nice to go inside the wall but the interior was completely taken over by very tall nettles, so went further along the road got into a field and proceeded up the long ramp of a mound that approaches the broch from behind. From the 'hilltop' there you look directly into the structure. Lovely it is.
Stone avenues between here and the Little Howe settlement at the coast are only the product of field clearances. RCAHMS NMRS number ND49SW 1 also reports that indications of structures about it are rather later. If so why does the mound lead up to the broch instead of more generally about it? I remember that Mine Howe is said to have been reached via one of the other mounds - perhaps it wasn't simply a case of this being the only dry route at the time.