As of 2010 the forestry to the south of the summit has been harvested leaving good views of the broad northern end of the Blackstairs.
An easy way to start is from the SE at Kilbrannish Forest Recreation Area car park at around S842568 A. Follow a marked track which goes generally NW towards the summit which is around 1 km away.
It is also possible to start from the less formal car park at Corrbut Gap S832568 B, walk uphill (north) with the forest edge on your left. Continue in the same direction after crossing a forest track to reach the top.
It is possible to use forest tracks as shown on OSI Mapsheet 68 to reach Greenoge to the east. Linkback: https://mountainviews.ie/summit/602/comment/5361/

We tackled Croaghaun after completing Greenoge -- see that comment for parking info. Sheet 68 appears to be accurate in its depiction of the tracks. The summit of Croaghaun is a bend in a forest track, with recently-felled ground to the left and forest on the other sides. It's not particularly inspiring, and the fog made it even less so. Ah well, another one in the bag, and as consolation, a small herd of deer did put in an appearance. Linkback: https://mountainviews.ie/summit/602/comment/2843/

Not a particularly attractive hill, but easily accessible. I did a loop walk taking in Greenoge along a good forest track across Kilbrannish Hill. One interesting aspect of Croaghaun is the presence of a standing stone over a stile about 50m along the track north of summit area. Standing stones are something of a curiosity, as little is known of their intended function. It is believed that rituals and other ceremonies would have been carried out around them. Apparently in the middle ages and later, people believed that as long as they were still standing, no bad luck would befall the locals in that area. Standing stones vary in date from about the late Bronze Age period to the Early Iron Age period. Linkback: https://mountainviews.ie/summit/602/comment/23365/

At the Corrbut Gap to the south of Croaghaun there's a large litter-strewn car park at point S832568 B. Loads of TV sets have been abandoned here, which is rather pointless - the miscreants could have saved themselves the bother of driving up here by dropping them off at any Powercity or D.I.D.
Having jumped the gate across the road, we walked uphill (north) with the forest edge on our left. After a short while we crossed a forest track but kept going uphill to the underwhelming summit marked by an old wall at a right-angled turn in a forest track. It took about 15 minutes from the car park to the top. Linkback: https://mountainviews.ie/summit/602/comment/4562/

On 3 May 2013 we parked at the purpose made parking area for the Kilbrannish Looped Walk S8431156818 C and after a short walk up a stoney path to join the main track we followed the waymarked trail (purple arrows) in an anti-clockwise direction. About 1.5 km along the looped walk turned up left W S855575 D. (Before continuing we detoured out and back to Greenoge. For details see my comments on Greenoge). Continuing up the purple trail we then went N and, a short way along, W again crossing the top of Kilbrannish Hill (Pt. 404) at S846574 E) actually on the track. Once up out of the trees we had views, somewhat restricted by mist, across to Mt. Leinster and it's E ridge leading out to Blackrock Mt.. Where the looped walk turned sharply down to the left at S8355057600 F we had to continue along the main track for about 100 metres to the top, an undistinguished high point along a raised ditch running parallel to the path. Once back at the looped walk we descended steeply down S and then ESE to the start. In all, including the 2k detour out and back to Greenoge, the walk took us two hours and was just under 8km in total. A pleasant introduction to four days walking in the Blackstairs. Linkback: https://mountainviews.ie/summit/602/comment/15056/