When my brother, sister and I searched for our Moynahan roots in Ireland in 2019, the Kerry locals directed us to the Sliabh Luachra area on the Cork/Kerry border. "That's where the Moynahans are" said the owner of O'Carrolls Cove Restaurant (Kenmare Bay) and sure enough, we found three cemeteries and many, many Moynihan's/Moynahans there.
I researched the Sliabh Luachra area and learned that this area was also the ancestral grounds for a Dr. Albert E. Casey (1903-1982), an Alabama pathologist, who collected Irish records from this area obsessively through the 1900s and published them in a 16 volume collection called, "O'Kief, Coshe Mang, Slieve Lougher and the Upper Blackwater"
Fast forward to October 2020, the Essex Branch of the Ontario Genealogical Society invited the Olde Sandwich South and Area Historical Society (OSSAHS) to give a presentation for their October 2020 meeting and I learned that some other Irish settlers in Sandwich South (Ontario) were from the same Blackwater area in Ireland as well!.