The most common and most likely answer to this crossword clue is the 8 letter word PARISHES
I've seen this crossword clue in The Daily Telegraph
P
A
R
I
S
H
E
S
More clues leading to the result PARISHES
Buddy explains!

The straight part
We know that "areas with churches" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case areas with churches = parishes.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does PARISHES mean?
PARISHES noun- In the Anglican, Eastern Orthodox, Lutheran and Roman Catholic Church, an administrative part of a diocese that has its own church.
- The community attending that church; the members of the parish.
- An ecclesiastical society, usually not bounded by territorial limits, but composed of those persons who choose to unite under the charge of a particular priest, clergyman, or minister; also, loosely, the territory in which the members of a congregation live.
- A civil subdivision of a British county, often corresponding to an earlier ecclesiastical parish.
- An administrative subdivision in the U.S. state of Louisiana that is equivalent to a county in other U.S. states.