A ley line is a purported geographical feature that connects sites of magically charged architecture. Believers claim that many important sites, such as Stonehenge, are connected together in a series of lines that contain great power or energy.
The term "ley line" was coined to describe alignments of landmarks that amateur archaeologist Alfred Watkins discovered on a map of Blackwardine, England. His 1922 book, "Early British Trackways," contained the first description of these purported lines, minus any mention of magic or spirituality. His theory was that the lines were simply trade routes that developed out of ancient peoples using line-of-sight landmarks to navigate.
In the late 1960s, ley lines were popularized and became part of New Age spiritual beliefs. John Mitchell reintroduced ley lines to the public during this period, adding the concept that these lines carry spiritual energy.