I became friends with a Polish historian.
He told me that the law in Poland is that there must be a search for artifacts before new highway construction can begin.
The firm that he was employed by performed the searches and would find ancient relics and burial grounds from many different eras in history.
Many of the items would end up in museums.
Of course they could also find live munitions left over from WW ll.
But that only represents a very small part of what they were searching for.
They would find relics dating all of the way back to the early middle ages.
Years ago, when a new building was being built in CT, some excavation workers uncovered a fossil bed that contained many dinosaur tracks.
A dome was built and the area containing the tracks was turned into a state park.--->>>
http://www.dinosaurstatepark.org/