My experience would call for approx 150-200 attending. Greatly depending on the nature of friendship established or family relationship.
Have A Great Celebration!
I agree with Blair. With the long drive, 150 to 200 seems probable.
It would be more if you took the factor of the long drive out of it.
If all conditions were perfect ( good relationships, great weather, short drive) with a 400 count invitation list, you would probably come in at around 300 to maybe 320.
And you will have those that RSVP they're coming, and don't show. Don't take it personally. It's inevitable. Things come up.
Best wishes for a great wedding!
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