The most common and most likely answer to this crossword clue is the 10 letter word TREE-LINED
T
R
E
E
-
L
I
N
E
D
Buddy explains!
The straight part
We know that "Like many French roads" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case like many french roads = tree-lined.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 TREE-LINED mean?
TREE-LINED adjective- Lined with trees.