Ground had scarlet buildings (10)

I believe the answer is:

cathedrals

'buildings' is the definition.
(cathedral is a kind of building)

'ground had scarlet' is the wordplay.
'ground' indicates an anagram (grind the letters ).
'had'+'scarlet'='hadscarlet'
'hadscarlet' is an anagram of 'CATHEDRALS'.

(Another definition for cathedrals that I've seen is " religious places".)

I've seen this clue in The Guardian.

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