Adding on to the post below, I found this note of Burl's.......
About three-quarters of a mile WSW of the Beekhampton roundabout on the south side of the road where the outline of the Roman road crosses the A4 there is an inconspicuous stone. It marks the place of a former gibbet.
Around 1837 the Royal Mail coach was held up by a gang of highwaymen and the driver. Henry Castles, murdered. The robbers made off towards Beckhampton but meeting a drunken labourer, Walter Leader, they stunned him and dumped him and a pistol alongside the wrecked coach and dead driver. Conclusions were quickly reached and Leader was condemned to death. On a misty December morning he was taken to the gallows where the crime had been committed and hanged. Minutes later a horseman arrived with a reprieve. One of the highwaymen had confessed. Leader was taken down and buried beneath a lonely tree nearby.
Burl, A., Prehistoric Avebury. Second Edition, New Haven and London, Yale University Press, 1979 Page 58
Maybe the ghost of Walter Leader has a thing about traffic.
Katy Jordan describes her spooky experiences on the Beckhampton to Devizes road in her book 'The Haunted Landscape':
At one time I used to travel this road quite often at night, and after passing the Beckhampton roundabout I would usually start to feel uneasy, as if there was something in the car behind me, and I would find myself looking in the mirror to check. This feeling of uneasiness would not lift until I crossed Wansdyke, and for some reason I always associated it with the round barrows in the area. Quite recently, and without knowing of my experience here, my friend Alison Borthwick told me that she often hears people calling to each other on just this section of road.
I spotted nine of the Barrows making up the cemetery whilst driving north along the very busy A361.
Four were on the brow of the hill, one south of a copse of trees and four in a line right next to the road.
Time was against us and parking is difficult on this stretch of road so I settled for a view from afar. To be honest, the four Barrows closest to the road are very easily seen and gives as good a view as you are likely to get.
I hope to visit the Barrows on top of the hill on a future visit but will approach from the other side of the hill - via Cherhill and Oldbury Hillfort.
When dashing along the road between Devizes and Avebury you will no doubt notice the wealth of barrows in the fields around you. About 24 of them (some now obvious, some ploughed out) made up the North Down cemetery. The oldest barrow was a Neolithic long barrow (now only 20cm higher than the surrounding field, according to the EH smr) – it was excavated in 1964 and three ox skulls were discovered inside, along with the wattle frame used in its construction. (Three ox skulls were similarly found within nearby Beckhampton longbarrow). The ground underneath showed that the area had been used for agriculture and 'funerary activities' before the barrow was built. The barrow was 40m long and orientated NE-SW (perhaps in reference to the midwinter sunrise?).
A bowl barrow was built in the Bronze Age close to the longbarrow, and around this focus were built the many other round barrows of the cemetery, probably over a considerable period of time. The cemetery is classic "DAD will you look at the ROAD" territory, so be careful because other drivers seem to use this straight stretch as a racetrack.