This monument is not in the Archaeological Inventory of County Cavan, published in 1995.
This is the entry on archaeology.ie:
Class: Cairn - burial cairn
Townland: POLLAKEEL (Upper Loughtee By.)
Scheduled for inclusion in the next revision of the RMP: Yes
Description: Located on top of Slieve Glah. A trig. station is constructed on top of a grass-covered cairn (diam. 13m; max. H 3m) that has been partly quarried, but there are indications of a small rectangular cist in its upper surface. It was reported by Michael Gibbons and Jim Higgins.