This is the Legananny Dolmen, one of the most spectacular megalithic monuments in Ireland.
On the slopes of Slieve Croob, it has a fine view of the Mountains of Mourne:
You have to bring your own child, though.
I had vaguely known for many years of a large souterrain, an artificial underground chamber, somewhere in the vicinity of the dolmen. To my delight I discovered this morning that it has been refurbished and is now open to the public.
Since it's halfway up a mountain and underground, an imaginative solution for giving visitors adequate illumination was needed. In this picture of the entrance you can see on the right the solar panels which power the lights:
Inside it's about 30 metres long, but only 1.5 metres high at the highest point. This makes it a little uncomfortable for those of average size and above, but smaller people will have an enjoyable visit:
Will bring a torch next time to peek into inaccessible corners.