County Kerry on Wikipedia.

Ardfert, the ruins of St. Brendan's Cathedral. © Christopher Skottowe (1965). Link1. Link2.

Ballybunion, Catholic Church. From an old postcard in Reg Dosell's Collection.
Ballydonoghue, St. Teresa. Previously in the "Unknown" section. Cathy Umbers, on behalf of a friend, was hoping to get an identification for a church in County Kerry, probably near Lixnaw (though it definitely isn't Luxnaw church itself). Although they obtained the identification though other sources, I'm glad to be able to include the solution here.
Ballyferriter, Gallarus Oratory. It's true purpose and date have been subject to much speculation. Link. The ruins of  Kilmalkedar Church. Link. Both © Christopher Skottowe (1965).

Cahirciveen, the O'Connell Memorial Church (interior view only). From an old postcard in Reg Dosell's Collection.

Kenmare, Holy Cross (R.C., 1864). From an old postcard in Reg Dosell's Collection. A modern view, © Dennis Harper (2006). Link. Church at Bunane. Interior view. Both © Dennis Harper (2006).
Killarney.
Killorglin, St. James (R.C.). Interior view. Both from old postcards in Reg Dosell's Collection.

Listowel, St. John (CoI) on The Square. From an old postcard in Reg Dosell's Collection. It's now in use as a theatre (link). Just a stone's throw away is St. Mary (R.C.), © John Balaam (2022). Link. The history page dates it to 1829.

Muckross, Muckross Abbey. From an old postcard in Steve Bulman's Collection. An "interior" view, © Christopher Skottowe (1965). Link. Holy Spirit. An Irish church, photographed during a 1970 family holiday, from Chris Scales' collection. Previously in the Unknown section, it was identified by Tony Preston.        

Tralee, Dominican Church of the Holy Cross. © John Balaam (2008). St. John (R.C.). © John Balaam (2008).