Knockreagh is the northern outlier of the summits which circle Grantrasna.

From the west, on the R571, there is a gated farm track at V80519 60522 A with room to park one car without blocking the entrance. From here the track leads almost to the summit and an out-and-back from here should take less than 90 minutes. Knockreagh could also be approached from parking deep within Glantrasna itself, at V82637 59648 B, although this involves some steep overgrown ground, particularly at the lower reaches.

A more complete route is to take in the summit as part of a circuit of the entire valley. Parking at either point allows access to a round taking in Knockreagh, Coomnadiha, Caha (not MV-listed), Droppa and Cummenbaun. In either case an amount of road-walking will be necessary. The entire circuit should take around 6 hours. Linkback: https://mountainviews.ie/summit/456/comment/5215/