[masswerk]

If they were cathedrals, this may raise the question why those towns were perfectly aligned, in the first place.

Traditionally, it had been mostly exposed locations that were dedicated to St Michael, e.g., locations that had been alleged entrances to the underworld in antiquity. 6 out 7 of these locations are in costal areas, with corresponding erosion features. So this shouldn't be of much surprise, as the line crosses several costal regions – of which there are plenty.

(In other words, the line crosses 6 costal areas with a St Micheal nearby and 6 without. The second fact may be as remarkable as the first one.)

Edit: Challenge, can we identify a "St Michael's Serpent", approximating a sine wave?