This is one of the few portal tombs in Cork, the only other that comes to my mind is Ahaglaslin near Ross Carbery.
Although the tomb lies only 140m north of the R592, it's not easy to find, because you have to climb over (or slip under, which I found easier) barbed wire and the tomb itself is quite overgrown and therefore difficult to spot. Park the car on the road shoulder that is on both side of the road just before you reach the highest point, when coming from Altar. Climb the hillside north of the street near to the highest point to the barbed wire and look for a farm track. Follow this track north, then northeast that goes around a small stream. You should see the top of the tomb poke out close to the base of a cliff.
The tomb tilts pretty sideways, maybe the soil moved downhill a bit during the thousands of years, since it was built. Behind the capstone, which rests on the portal stones, is another (pretty overgrown) capstone, that lies over the chamber.
From the tomb you have a terrific views to Toormore Bay and the gurgle of the nearby stream also contributes to the delightful ambience of this site.