From the Tap O Noth car park head up the path over the stile and keep going till the old wall. A track of sorts heads east, follow this for about 200 meters and the grass covered cairn can be seen with two or 3 possible kerbs in place. Little is heard of this cairn which stands at approx 8/9 meters in diameter and would be just below 1 meter in height. (I found it by chance on an old map and Canmore doesn't list it tho it appears on their map, sadly with no name)
Sadly this is a very badly damaged cairn with agriculture and the beasts having a fair go at destroying it. Still it remains in prehistoric central surrounded by forts, circles, cairns, standing stones and loads of cup marked rocks in the Brawland/nearby areas.
(Just an observation, the cottage near the car park, what a dump you'd seriously think somebody with some clout might tidy it up. What a shambles for visitors to see)