It would require massive work by large teams, financial support and lots of time, since energy-lines fluctuate and move in ways that no one has fully been able to study. Surveying and compiling a map of dowsable energy lines would be complex and possibly unachievable.

There can indeed be a certain geomantic 'twang' to alignments, but it's not the same as dowsable earth-energy lines, which move in very naturalesque, non-straight ways. Alignments and energy-leys are different things and should not be confused. The existence of a line on this map does not necessarily mean it can be dowsed today, though some can. They 'plugged' their sites into the network by carefully locating, designing and aligning their earth, stone and wood constructions. The ancients presumably saw energy and significance in such alignments. They simply show alignments of ancient sites and natural features, as identifiable on detailed Ordnance Survey maps. The alignments on this map do not show 'energy lines', identifiable by using dowsing, sensitivity or 'second sight'.

Glastonbury tor location map