Secrets of Ancient and Sacred Places by Paul Devereux
Blandford UK 1992
This is an excellent text on the subject.
The book mentions the growing movement in archeology to include concepts from geomancy. It discusses the major findings of the Dragon Project, which was organized to sift fact from fancy in the rumours of ancient sites. Using scientific monitoring, this project has concluded so far that
1) The location of stone circles in Britain, and apparently many monuments around the world are in close proximity to geological faulting.
2) Magnetic anomalies, including low level periodic magnetic fluctuations in specific stones; and permanent magnetism of certain rocks due to high iron content.
3) Natural radioactivity occurs in a number of sites; especially high concentrations of radon.
The book characterizes several significant aspects of "Places of Power":
The book includes the results of a analysis of a number of United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Heritage Sites, evaluated in terms of these specific criterion.