County Derry or County Londonderry on Wikipedia.

Ardmore, St. Mary (R.C.). © Mark Lusby.

Ballinderry, St. John (CoI). © Gerard Close.
Ballymaguigan, St. Trea (R.C). © Murray Lynn.
Ballyronan, St. john (CoI). © Gerard Close.
Banagher (R.C.). © Mark Lusby.
Bovevagh, Presbyterian Church. © Gerard Close.

Derry City.

Garvagh, Main Street Presbyterian Church, founded 1773. The Presbyterian Church's motto "Ardens Sed Virens" - burning yet flourishing" is included on the church information board. St. Paul (CoI). C 839 159. Both © Gerard Close.

Lavey, St. Mary (R.C.). This is the "new" church, dedicated in 1873. © Mark Lusby.

Macosquin, Presbyterian Church. C 844 270. © Gerard Close.
Maghera, Presbyterian Church. H 851 002. © Gerard Close.
Magherafelt, Calvary Free Presbyterian Church. H 881 911. © Gerard Close. Link.
Moneymore, St. John. 1st Presbyterian Church. Both © Gerard Close.

Swatragh, Presbyterian Church. C 859 079. © Gerard Close.

Tamlaght O'Crilly, St. Mary (R.C.) aka Drumagarner Chapel. Janice advises that it was built in 1778, burned and repaired in 1810, and more or less completely re-built in the mid 19th century. Interior view. Both © Janice Bacino.
The Loup, Saltersland Presbyterian Church. St. Patrick (RC). H 903 844. Both © Gerard Close.
Tobermore, The Carson Memorial Baptist Church. Presbyterian Church. H 830 966. Church of Ireland. H 823 962. All © Gerard Close.