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It's in Belgium, also in Spain (3)

Ross

I believe the answer is:

spa

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'spain' is the definition.
The answer and definition can be both locations as well as being singular nouns.
Perhaps you can see an association between them that I don't see?

I don't understand the remainder of the clue.

Can you help me to learn more?

(Other definitions for spa that I've seen before include "Mineral-water resort" , "hydro" , "here for the good of his health?" , "Boston" , "Watering place" .)

I've seen this clue in the Evening Standard.
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