IF you are near Devizes between April and September, chances are you could be lucky enough to see at least one of those amazing formations that appear in arable fields known as crop circles.

Every year for almost 20 years, investigators from all over the world have descended on central Wiltshire to examine the phenomena which appear, apparently overnight.

They can be up to 700 feet across and of an extraordinary design and complexity. They turn up in fields of oil seed rape, wheat, barley indeed, any growing crop that will sustain them.

Simple circles, or lines of circles, in growing crops have been known for centuries, thought to be created by small whirlwinds that occur regularly when rising temperatures set up convection currents. Then, in the early 1990s, pictogram shapes began to appear on a regular basis, and they have been growing in number and complexity ever since.

In 2003, some 72 formations were reported in England, most of them in the south and by far the largest proportion in the area between Devizes and Marlborough.

The largest formation of 2003 appeared in a wheat field on the North Downs, near Beckhampton, on August 10.

It measured 670 feet across and depicted a chain of crescents around a central circle.

Opinion is evenly split as to the origin of these creations.

Crop circle investigators from all over the world, including some very high-profile names from the world of literature and show business, are firmly convinced these are the work of an extra-terrestrial power trying to communicate with us.

But there is also a group who claim to have created the circles, sometimes within sight and earshot of investigators, overnight, in the dark and with nothing more hi-tech than tape measures, ropes and sticks.

However you believe they were made, there is no contention that the results are, in the main, true art and a stunning addition to the already beautiful Wiltshire landscape.

For more information on circles and other strange phenomena, visit the website www.weirdwiltshire.co.uk or drop into The Barge,a welcoming pub at Honeystreet, where circle enthusiasts gather to swop notes on their discoveries.