Take the road south out of Kinnitty in the direction of Roscrea. Take the first turn left. Drive along this road for two miles until you see an entrance to the forest on the right. There is room to park a few cars here. Follow the forest road, keeping right at the Y junction. Ignore the next two right hand turns. Take the third turn right. This will bring you close to the summit, which is a grassy mound just off the forest road. Car to car takes less than an hour.
As of Jan 2022, the forest track ends and becomes a muddy trail for about 200m and to access the high point requires a trudge up through a recently-felled forest, over very uneven ground. The actual high point is difficult to pinpoint, which could be any of several rough bumps in the boggy terrain. Linkback: https://mountainviews.ie/summit/1124/comment/15368/

Was a little disappointed when I got to the flattish top of Cumber Hill and looked around for signs of a Hill Fort which I failed to find. There were a series of ditches which could have been the earthworks but no signs of stones. I did find 2 deer happily chewing on the heather and a tree at the cross roads of fences which serves as a suitable summit point. Linkback: https://mountainviews.ie/summit/1124/comment/15856/

Cumber Hill Hillfort earthworks1 Linkback: https://mountainviews.ie/summit/1124/comment/20482/

Cumber Hill hillfort earthworks2 Linkback: https://mountainviews.ie/summit/1124/comment/20483/

Thanks to recent forest clearance, at least the views from Cumber have improved, if not the ease of access. This is a wintry view from near the top looking towards Carroll's Hill. Linkback: https://mountainviews.ie/summit/1124/comment/23376/