Ruins Blackpool's first illuminations (7)

I believe the answer is:

blights

'ruins' is the definition.
(blight is a kind of ruin)

'blackpool's first illuminations' is the wordplay.
'first' says to take the initial letters.
'illuminations' becomes 'lights' (light is a kind of illumination).
The initial letter of 'blackpool' is 'b'.
'b'+'lights'='BLIGHTS'

(Another definition for blights that I've seen is " Causes to wither".)

I've seen this clue in The Telegraph.

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