Carrigroe is situated midway along the ridge that extends south from Blackstairs Mountain, between Carrigalachan and Bran Scultair. It is unlikely to be climbed on its own, and will probably merely be a waypoint for those traversing the ridge. A wide track like a white scar runs along the crest of the ridge, probably created by machinery for access to the forests on the eastern slopes.

A Coillte forest road begins at S758364 A. The barrier is usually open leaving the option to drive further into the forest. At S784393 B there is a track junction, with a track heading north for 1km directly to the summit of Bran Scultair. From the curious summit of Bran Scultair (a trig pillar perched atop a rocky tor), follow the ridge crest track 1.5kms north to the unremarkable summit of Carrigroe. Any one of a number of track-side stones could mark the high point. There are good views west to Brandon Hill and the plains of Carlow/Kilkenny.
An alternative approach is via Carrigalachan, starting at 809 410 C - see that short summary for details. Linkback: https://mountainviews.ie/summit/471/comment/5230/