The most common and most likely answer to this crossword clue is the 7 letter word CUMBRIA
C
U
M
B
R
I
A
More clues leading to the result CUMBRIA
- Brum, unlikely ‘guest’ of spy agency in north of England
- A mountainous place, Cuba, a mountainous place
- County allied with rose, briefly
- Cold part of Italy – or of England?
- County agents entertaining doctor in old city
- County and cold part of Italy
- Cold region of Italy or hilly part of England
- Carbon and barium mixed in Carlisle region
Buddy explains!

The straight part
We know that "A mountainous place" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case a mountainous place = cumbria.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.