03/15/2011 12:46 pm ET | Updated May 25, 2011

Stonehenge Secrets May Be Revealed By Laser Scan

Modern technology may be the key to unlock hidden secrets about an ancient monument: Stonehenge.

Researchers are using lasers to scan the nearly three dozen stones, or megaliths, that make up the famous circular complex on the Salisbury Plain of southern England.

The vertical stones -- over 10 feet tall and weighing many tons -- form the site that's believed to be nearly 5,000 years old. And nobody is sure why or how Stonehenge was originally built.

"This new survey will capture a lot more information on the subtleties of the monument and its surrounding landscape," said Paul Bryan of English Heritage, an adviser to the British government on historic buildings and monuments.