Using powerful ground-penetrating radar, which can ‘x-ray’ archaeological sites to a depth of up to four metres, investigators from Birmingham and Bradford universities and from the Ludwig Boltzmann Institute in Vienna have discovered a 330 metre long line of more than 50 massive stones, buried under part of the southern bank of Durrington Walls.
“Up till now, we had absolutely no idea that the stones were there,” said the co-director of the investigation Professor Vince Gaffney of Birmingham University.
The geophysical evidence suggests that each buried stone is roughly three metres long and 1.5 metres wide and is positioned horizontally, not vertically, in its earthen matrix.
However, it’s conceivable that they originally stood vertically in the ground like other standing stones in Britain. It is thought that they were probably brought to the site shortly before 2500BC.
They seem to have formed the southern arm of a c-shaped ritual ‘enclosure’, the rest of which was made up of an artificially scarped natural elevation in the ground.
The c-shaped enclosure – more than 330 metres wide and over 400 metres long – faced directly towards the River Avon. The monument was later converted from a c-shaped to a roughly circular enclosure. (source)
I have indicated the approximate position of these hidden dragon's teeth with a line - click to enlarge.
It must be emphasised that these are only geophysical echoes at the moment - we have no idea what is actually buried there. It echoes like stones and they seem to be below the ancient bank but without actually digging down we won't know if what they are or from when. I just hope they aren't something the Army dug in during the last European Unpleasantness .
It is also worth noting the emphasis given to the C shaped nature of Durrington Walls. This is based on the (enhanced?) scarp that surrounds the natural valley that runs up the middle of the henge, maybe to what was a winterbourne spring, The bank and ditch tend to be either side of this scarp to the north and west, and would seem to be later. As Vince Gaffney said Durrington Walls is a very three dimensional monument and flat maps deceive. The original map form the the 1960s excavations shows the scarp and contours well.
Click for huge version