It could have been The Griswolds knocking over Stonehenge with their car in National Lampoons European Vacation in 1985!

Newgrange was only a few miles away from where I grew up so I'm sure that it figures somehwere but without a specific memory I dont think it can qualify :( I did bring my wife-to-be there on our first proper date though!

I do remember being fascinated by the mysterious Knowth and Dowth when our teacher explained they were just as big and old as Newgrange but were not visited. At that time we were told Newgrange was the oldest building in the world or something like that, didn't have a clue for years what was really out there and thought Newgrange was a unique freak of history.