This is the first site you come to when walking up the path from the car park towards the famous stone circles. It is an Historic Scotland site and as such has metal railings around it and an information board. It is a 15 minute walk from the car park - about the half way point to the stone circles.
There are several large kerb stones still in place and the large, low, grass covered stony mound is clear to see. The cairn is in a lovely setting with mountains in the distance. If this cairn was anywhere else it would get a lot more attention than it does here. The draw of the stone circles move people on far too quickly.
The superstitions of the Arran people are deeply imbued with the legends of fairy mythology. The perforated column of "Fion=gal's Cauldron Seat," on the Mauchrie Moor, was believed to contain a fairy or brownie, who could only be propitiated by the pouring of milk through the hole bored in the side of the stone.
p67 of 'The Antiquities of Arran' (1861) by John McArthur.
"Is it a stone circle with a later burial cairn built inside it or is it simply a cairn with a permanent stone kerb?"
Don't be daft. It's Fingal's Cauldron Seat, made by Finn McCool. He sat here while he cooked his tea.
There's a holed stone in the outer circle - this is where he tied up his dog Bran, to stop him making off with the stew before it was cooked.
(from the Atlas of Magical Britain, by J+C Bord)
In one of the stones of Fion-gal's cauldron seat - Suidhe choir Fhionn - there is a remarkable perforation, which was probably associated with some old superstition or religious ceremony, now forgotten. The hole is sufficiently large to admit the two fingers, and runs perpendicularly through the side of the column. Tradition relates that to this stone Fion-gal was wont to tie his favourite dog Bran.
From p55 of 'The Antiquities of Arran' by John McArthur (1861).