Looking for Dublin Church with Mummies

Hi,
Years ago, I was in Dublin and visited a church which, due to basement conditions perfect for mummification, contained the mummies of a crusader and a few other people. For some reason, St Michael's sticks in my head, but I'm not sure if that is correct. I cannot find a reference in Rick's Ireland book or anywhere else. So, can any of you let us know which church I am thinking of? Thanks!