Park at V80498 57651 A, small layby room for 2 cars. Go through the gate and walk downhill past a house and up into Glenrastel. As you enter the valley, keeping to the right of the river, note the distinct zig-zag track descending Pookeen to your north. This is your way down from Cummeenbaun. Walking up the valley cross the river at a low rock shelf(Mccools step) and leave the river bank ascending due north. As you gain a rocky, slabbed ridge turn west for Cummeenbauns summit. Descend via the zig-zag path. Linkback: https://mountainviews.ie/summit/431/comment/5190/

If you have ascended the indistinct lump called Caha and then go west towards Cummeenbaun you can savour 3k of one of the most remote and interesting ridges in the Cahas or anywhere in Ireland.
The southern side is much less steep than the northern however it is steeper than the equivalent side of the nearby Cusnaficulla-Knockowen ridge, which is somewhat similar.

Around 800m east of Cummeenbaun you will come to the unsung, but spectacular Droppa. What an unusual name. Paul Tempan supplied the following information about it.

"The anglicised form Droppa could come from the word 'dreapa' meaning
'climb' or 'place suitable for climbing'; it can also mean 'ledge' or
'crevice' (in a cliff). The Irish words for rock-climber 'dreapadóir' and
rock-climbing 'dreapadóireacht' come from this. This interpretation would
fit with the topography.

Regarding the Irish version, the name Struice an Iolair is found on the old
"Killarney District" map, not at this point but at a higher spot near Caha,
and Eagles Nest is given as the English version. The Killarney District map
is generally less authoritative than the later Discovery series, but in
this case it would appear to be more plausible."

Our photo shows the axe-head top and steep north side of Droppa from the east, with Cummeenbaun in the background. Linkback: https://mountainviews.ie/summit/431/comment/2246/

Parked on a bit of muddy grass next to the road at V826 597 B, as suggested by Simon3 above. There is a gated bridge over the Glantrasna River, and a road leading up to a farmhouse on the right. Looked about for a farmer to ask permission, but none to be seen, so went through gate and turned left along a short track for about 30 metres, then crossed a fence into a grassy field and began to ascend the steeply rising slope in a SW direction. After about 100m the going became a bit tougher - long reedy grass and quite muddy underfoot. Proceeded in this direction for about 1km, then began to curve round to the western side of the summit, where the terrain became a lot more rocky and quite steep for about 200 m (Point 818 583 C). The slope eases considerably during the last few hundred metres and the summit itself is a distinctive grassy bump, which is otherwise unmarked. There is a great view of Droppa, which because of its lack of prominence, is not recorded on any of the mountain lists, yet presents a beautiful and impressive wall of rock plunging hundreds of metres from a pointed summit. Two hours completed the journey up and down. Linkback: https://mountainviews.ie/summit/431/comment/14880/

There's space for a few cars at V82621 59671 D near a bridge. As of 2006, the road to there has been relatively recently resurfaced. Further up the valley there are some apparently abandoned houses. From here you could, for example, walk somewhat circuitously by road to Knockreagh or go directly to Cummeenbaun, perhaps using the route shown in the simulation (courtesy OSI TrailMaster) Linkback: https://mountainviews.ie/summit/431/comment/2247/

The ridge heading north from Cummeenbaun descends steeply into Glantrasna and provides both an ascent and descent route to the Summit. Parking is deep in the valley at V82627 59648 E Linkback: https://mountainviews.ie/summit/431/comment/18205/

I have given some thought as to how to get to this much lauded spot (Cummeenbaun) while taking in the maximum number of Arderins and VLs along the way. Track 3036 is a 20k Onzy track which develops simon3's earlier Track 1963. Onzy's Track could be extended without too much extra work to Killane Mountain, as an out and back.
I have thrown together a plan that might work too, but before I do anything else I'm going to add the AAs and VLs and see what gives the biggest bang for buck.
Track 3036 as walked by Onzy: takes in 3 Arderins of which one is a VL; Knockreagh , Coomnadiha and Cummeenbaun, plus 3 'Arderin Beg' summits, Droppa, Caha FSET and Caha SET (which , by the way, don't count in my book)
Track 3036 extended to Killane: as above, adds another AA and an AB (total 4 Arderins of which one is a VL)
My suggested route: 4 Arderins of which one is a VL.. Can't see that my idea advances things very much!

UPDATE: 13th June 2016. I had to pop down to Kerry at the weekend to collect my bike so I legged it up Knocknagorraveela as an out and back. This now frees me to to tackle Onzy's above Track BUT with the Killane Mountain add on. It will be a long but I suspect rewarding route if I manage to pull it off. I have done a quick tot of the ascent and it doesn't seem overly arduous from that point of view. We shall see. Chickens should never be counted until they are at the proof of the pudding stage. Linkback: https://mountainviews.ie/summit/431/comment/18571/