An update on the Old Straight Track by Alfred Watkins. Danny Sullivan rightly admires Watkins' original text and does a good job of bringing it back to our attention (I read it immediately after Ley Lines).
However, as Sullivan points out, the concept of 'ley lines' has been hijacked by the same 'mystical tribe' who see alien origins in crop circles and can infer a whole cultural certainty around the Druids and 'Paganism' from the few surviving fragments of Roman text. What I'm not certain of is to what extent the author is himself convinced by these beliefs. However, he does a good job of balancing the two sides of the coin.
This book allows the reader to examine what they believe about ley lines (or not) and to clear out all the distracting tribal noise before reading Watkins' more comprehensive work on the subject. Considering the era in which it was written (Watkins is essentially a late Victorian polymath) it is remarkably self effacing and does not make too many assumptions about what is clearly there on the ground.
Ley lines are a fascinating subject for the historian and the more open-minded professional (or amateur) archeologist, and reading both of these books is an illuminating start on the subject. The two categories of people who won't benefit from either are the traditional archeologist who is sniffy about anything tainted by beliefs and the tribal mystic whose beliefs allow them to see whatever they want to. The care one needs to exercise is to not fall into either of these categories.
The very least you will do having read this book (and hopefully the Old Straight Track) is to get out for more walks and to notice more in the landscape.