Q WHAT can you tell me about ley lines? - William Sewell, Bishop Auckland.

A Ley lines are a controversial subject and many experts refute their existence, attributing them to selective coincidence. Ley lines are perceived as lines of energy that have existed since ancient times. This belief gained popularity during the UFO crazes of the 1950s and 1960s.

Determining whether ley lines exist depends partly on what a ley line is considered to be. The most basic explanation is a straight line that appears to link several sites of ancient origin. Ancient sites, in this respect, are usually those of pre-Roman origin. However, more recent features like churches or castles are also included.

Ley lines were 'discovered' in 1921, by 66-year-old Alfred Watkins, of Herefordshire. Watkins was a partner in a firm of millers and travelled widely in his county. He noticed that many ancient sites in his neighbourhood stood along definite straight lines. Watkins called the lines ley lines because many places along them had names containing the Anglo-Saxon word ley or leah. This word usually means a clearing or glade in a wood.

Watkins identified a number of categories for the sites found along the lines. These included ancient mounds, like barrows, cairns and megalithic tombs; ancient stones, like standing stones or stone circles; ancient camps or hill forts and water markers like circular moats, ponds or ancient fords. Ancient wells and crossroads (long regarded with great superstition) were also included in Watkins' analysis, as were ancient trees or tree clumps.

Watkins was particularly interested in beacon sites that he thought often appeared at the beginning of a ley line. It was implied that the ancient surveyors who originally constructed the ley lines used beacons of flame.

Watkins' view of ley lines was that they represented trackways used by traders rather like himself. In recent times, some experts conclude that ancient man regarded the trackways in a more mystical sense, as route ways for the spirits of the dead.

Of course, there are many who do not believe in ley lines at all, pointing out that the more features you include and the longer you draw a line, the more likely you are to find coincidental links that suggest a line.

If you have a Burning Question, or can improve on the answer above, please write to Burning Questions, The Northern Echo, Priestgate, Darlington, DL1 1NF or e-mail david.simpson@nne.co.uk