Although I have already posted this picture to Britarch in response to the "UNITY" thread I repeat here because I have gathered that some on the list did not get the post in their mailbox. Maybe there is something erratic going on.
The story began with Orion reminding us that, from MPP's words, there was some possibility of a spring at the level of the Stonehenge site (104m osl) or higher. I happened to be working with the Scottish NLS map site studying the area near Stonehenge and switched to terrestial view which is labelled "Bing Copyright 2015". I assume this satellite view in the public domain is a recent one. I have enhanced it UNIFORMLY in Photoshop to emphasise the differing green colours. I have not selected any area to the west of Rockhenge for specific enhancement. Here is the picture.
I am rather inclined to believe there was extra moisture in the ground to the west of the ring. It could have been once a spring and maybe quite a substantial one in neolithic times (I'm told...). I have added a few contours from the "gov" lidar files in order to show that the damp area does seem to be coordinated with levels.
Could this be the prompt for ground work, first guided by a moisture survey, to find a convincing piece of evidence to support the stonehenge moat theory?