The most common and most likely answer to this crossword clue is the 8 letter word GROTTOES
I've seen this crossword clue in Independent
G
R
O
T
T
O
E
S
Buddy explains!
The straight part
We know that "Caves" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case caves = grottoes.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 GROTTOES mean?
GROTTOES noun- A small cave.
- An artificial cavern-like retreat.
- A Marian shrine, usually built in a cavern-like structure.
- A local organization of cavers that typically organizes trips to caves and provides information and training for caving; a caving club.
- (Satanism) A secretive name for a local group of underground Satanists.