Thousands of years ago, an ancient civilization raised a circle of huge, roughly rectangular stones in a field in what is now Wiltshire, England. Stonehenge, as it would come to be called, has been a mystery ever since.  Building began on the site around 3100 B.C. and continued in phases up until about 1600 B.C. The people who constructed the site left no written records and few clues as to why they bothered to schlep the stones to this spot.  Wild theories about Stonehenge have persisted since the Middle Ages, with 12th-century myths crediting the wizard Merlin with constructing the site. More recently, UFO believers have spun theories about ancient aliens and spacecraft landing pads.  What we do know is that surrounded by hundreds of round barrows, or burial mounds, the Stonehenge site is truly impressive, and all the more so the closer you approach it.  It is a place where much human effort was expended for a purpose we can only guess at.  Some people see it as a place steeped in magic and mystery, some as a place where their imaginations of the past can be fired and others hold it to be a sacred place.  But whatever viewpoint is brought to it and whatever its original purpose was, it should be treated as the ancients treated it, as a place of honor.  It is, however, Britain’s greatest national icon and a world heritage site and no trip to the area would be complete without a stop.