TheDazman
I visited the site of the now disappeared Longbarrow about 5 years ago. It is referenced on the Salisbury OS map.
I rarely see any internet posts regarding it’s proximity to Figsbury Rings, though I am as blind as a post. It’s approx 1/3 mile from Figsbury and in site of.
This suggests to me that Figsbury has a Neolithic precedent, as the Longbarrow is dated 4000 BCE.
Also, of interest, is that Clearbury Ring is visible from the barrow site.
Knap Hill from the slope North of Adams Grave.
Image credit: TheDazman