Celebration where men, animals and machines may be seen? (5-5)

'men animals and machines may be seen?' is the definition.
I know nothing about this answer so I can't tell whether this works.

'celebration' is the wordplay.
I cannot really see how this works, but
'celebration' could be 'party' (I've seen this in another clue) and 'party' is found in the answer.
The remaining letters 'after' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).

'where' acts as a link.

Can you help me to learn more?