This rath is across the road from a national school and not far from the main mound of Rathcroghan.
Herity's book describes it as "A wide deep ditch, 7m in weight, provided material for a bank 38.50m in diameter which encloses a small area with a convex surface at the top. There is a good deal of stone in the bank which stands out from the knoll in the profile of the monument towards the east. An entrance on the east side is placed opposite a causeway across the ditch".
Daith's Stone (Standing Stone / Menhir) — Fieldnotes
This stone is found by walking through a number of fields from Owenynagat. This is cattle country with high barb-wire fences and lots of beefy cattle so I would regard this walk as only for the brave.
According to Michael Herity's book on the area "The standing stone of red standstone is 1.85m high, 1.4m by 25cm at the base. This Coirthe Dearg, Red Pillar Stone, reputedly marks the grave of King Dathí (Nath I), nephew of Niall Noíngiallach, Niall of the Nine Hostages, who was killed by a flash of lightning on an expedition at the foot of Sliabh n-Ealpa".
Niall was of course the slave dealer that brought St. Patrick to the Irish shores (or some my memory of primary school history goes).
We visited this amazing site as part of last years Irish megameet. Access to the site is good, its up a lane and it seems to be ok to drive up and park beside it.
Thats the easy part, getting the courage up to slither in and see what is inside is another thing.
I understand that a reused ogham stone acts as the lintel to the souterain and this in turn leads to the limestone.
Fourwinds gives us a little bit on the massive folklore associated with this spot.
Id highly recommend bringing some clean clothes because it was very muddy inside and this was the height of a very dry summer so I would imagine that it could be dangerous during wet spells.