Richard Mersey who has written about this general area, known as the Dunkerrons said between Coomcallee and Knocknagantee "is an area wild and rocky with many lake on the summit ridge, and deep coums cutting from both sides." That about sums it up! There's lakes, coums, rough ground everywhere.
Brian Ringland [Interview in MountainViews] further talked it up. In answer to the question "Best experience on a 500 m walk?" he said "Coumcallee and east of that towards Knocknagantee. Lots of little lakes and wild, interesting country. Very tricky navigation in bad weather."
For a small party (up to5 say), one way of getting onto it is to leave the road at A (V671 698)
. Ask permission at the last house and walk NW on the track shown on the map that goes round the north end of Dromtine Lough. Then onto the ridge leading west and up.
With a larger party I would recommend starting around 600m north (near the "Standing Stones") or south perhaps at the forestry accessed from the main road at B (V673 686)
. Ask permission if you go anywhere near houses or cultivated fields.
As you ascend the ridge on a good day, longer and longer views appear on both sides. To the left Coomnahorna and the southern cliffs of Coomcathcun, to the right a view along a series of jutting ridges of the Dunkerrons. This includes Knocknagantee, the less well known Coomnacronia and Finnararagh (aka An Corrán). All wild spots.
The summit is on a slight rise above a broad and rough plateau with several lakes. There's a cairn. Linkback: mountainviews.ie/summit/313/comment/2484/