Wonderful work by Simon Banton.
In 1812, Sir Richard Colt Hoare (henceforth RCH) published "The Ancient History of Wiltshire, Vol. 1" - a magnificent work (one of a pair - volume 2 followed later) which detailed the work he sponsored and William Cunnington supervised in the years before and after the turn of the 19th century.
Aided by Stephen and John Parker, this ensemble excavated many hundreds of burial mounds across Wiltshire. It was one of the earliest attempts at scientific archaeological recording as opposed to simple treasure hunting. Many of the finds ultimately ended up in Wiltshire Museum and the descriptions of the barrows' excavations are a valuable resource.
There is a map in Ancient Wiltshire labelled "Stonehenge and its Environs", drawn by Philip Crocker, that depicts the landscape around the monument together with the barrows that had been investigated and numbered by RCH during this work. RCH also grouped the barrows into several areas in his "Stations" and "Itineraries" in the text, but not totally consistently in all cases.
These days, we don't use RCH's barrow numbers.
Instead there are several different standards such as the Goddard/Grinsell Parish Numbers (eg Amesbury G15), the National Monuments Record Number (eg SU 14 SW 104), the Historic England Monument Number (eg 219732) or the Wiltshire & Swindon Historic Environment Record Number (eg MWI12998 SU14SW835).
All of the above refer to the same barrow - one called "Sun Barrow" - which is RCH's barrow number 164 in his Amesbury grouping.
It can be a real challenge to correlate information that uses one system with other information that uses a different system. What's more, there isn't (or wasn't) anything online that allowed you to find a barrow via any of these systems and see the reference numbers (and links to) the other systems alongside.
That sort of thing tends to frustrate so Simon Banton created a Google Map backed by a Google Spreadsheet and set about matching up the data into a single reference work for the barrows shown on RCH's famous map.
There is a downloadable spreadsheet of the GoogleDoc data compilation so other people can play with / archive it. Just in case Google should ever go belly up, it'd be a shame if it held the only copy!
It's linked to in the copyright notice at the bottom left of the map's left column