The Craw Stane, on a PSA near Eaglesham, is believed to occupy a Bronze Age burial site. Inside the front cover pocket of the book there is a 48 x 40cm map showing the networks of PSAs radiating from Camphill, Crookston, Carmyle and the Necropolis, and how they combine with each other to form the larger Glasgow Network of Aligned Sites. It is unlikely that the PSAs on this map were all in use at one time. Re-occupation of popular sites after periods of abandonment seems more likely. PSAs were surveyed as single lines, not geometric figures or patterns.
Triangles are the inevitable result of a group of single lines crossing and recrossing each other.
The Glasgow Triangle is a convenient geographical term - it would not have been known as a triangle in prehistoric times. On the back of the Glasgow Network map there is a gazeteer of 70 sites with their O.S. grid references. Anyone who thinks PSAs are imaginary can compare them against the amount of sites to be found on a similar length of line anywhere on the 1600 kilometres of eastings and northings represented by the straight blue lines on the Ordnance Survey Survey Sheet 64 Map of Glasgow. Observe how PSA's cross and recross the same points of the landscape. It can be as narrow as a path between two stones,or as broad as the line of site to a distant hillfort.