The most common and most likely answer to this crossword clue is the 7 letter word CHAPELS
I've seen this crossword clue in Financial Times
C
H
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P
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Buddy explains!
The straight part
We know that "holy locations" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case holy locations = chapels.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 CHAPELS mean?
CHAPELS noun- A place of worship, smaller than or subordinate to a church.
- A place of worship in another building or within a civil institution such as a larger church, airport, prison, monastery, school, etc.; often primarily for private prayer.
- A funeral home, or a room in one for holding funeral services.
- A trade union branch in printing or journalism.
- A printing office.
- A choir of singers, or an orchestra, attached to the court of a prince or nobleman.