Archaeologists have discovered evidence of what they believe was a second Stonehenge located a little more than a mile away from the world-famous prehistoric monument.

The new find on the west bank of the river Avon has been called "Bluestonehenge", after the colour of the 25 Welsh stones of which it was once made up.

Excavations at the site have suggested there was once a stone circle 10 metres in diameter and surrounded by a henge – a ditch with an external bank, according to the project director, Professor Mike Parker Pearson, of the University of Sheffield.