Nostalgic memory of Vesuvius (AD79) (5,4,3,4)

I believe the answer is:

blast from the past

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'vesuvius ad79' is the definition.
I don't know anything about this answer so I cannot tell whether this works.

'nostalgic memory' is the wordplay.
I cannot quite see how this works, but
'memory' could be 'rom' (ROM is an example) and 'rom' is present in the answer.
This explanation may well be incorrect...

'of' acts as a link.

Can you help me to learn more?

I've seen this clue in The Guardian.

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