I saw Gary race around roads (12)

I believe the answer is:

carriageways

I'm a little stuck... Click here to teach me more about this clue!

'roads' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Maybe there's an association between them I don't understand?

'i saw gary race around' is the wordplay.
'around' indicates an anagram.
'i'+'saw'+'gary'+'race'='isawgaryrace'
'isawgaryrace' with letters rearranged gives 'CARRIAGEWAYS'.

Can you help me to learn more?

I've seen this clue in The Everyman puzzle in The Observer.

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