in relation to this thread today I went to check up a new place near, Lecarrow, midway from Athlone to Roscommon,
at the place in question there are the remains, ruins of castle Rinduin/Rindoon castle along with some remain
from old St. Jhons church, St.Jhons Hospital next to a graveyard .. there is also a long strecht of between 100-200 metres
long normand wall defense ... all this surround by the lake Shannon .. worth to visit.
The google maps link is: (just drop the human dummy at the crossroad junction of the three roads to see the directions for the castle.)

A link about the history around the castle: