Ley lines seem to be the most known, yet least understood of the geopathic stress phenomena. Ley lines are man-made energy lines, created by stone formations such as stone ships or other ancient archaeological structures. The knowledge of creating Ley lines is supposed to be lost. They appear to be connections between funerary, astronomical and geometric practices. They seem to link primarily (religious) shrines and temples and are most well known in England. Despite being ancient, they are incredibly precise.
The current definition of a Ley-line according to http//:Wikipedia.en.org/ is as follows:
'Ley lines are hypothetical alignments of a number of places of geographical interest, such as ancient monuments and megaliths. Their existence was suggested in 1921 by the amateur archaeologist Alfred Watkins, whose book 'The Old Straight Track' brought the alignments to the attention of the wider public’.
As with other eopathic stress phenomena, Ley lines can be tested for with dowsing. If you find your house sits on, or near a ley line, mitigation is the solution.
Source:
http://www.ancient-wisdom.com/leylines.htm
https://michelduchaine.files.wordpress.com/2013/07/ley-lines.png