It appears that whatever is not at the Louvre or at the National Gallery in London is here.   There are a lot of priceless sculptures here and a great many of them share the same story.  No one knows how some of these 2 or 3 or 5 thousand year old sculptures found their way to Rome but a lot of them were found in a private gardens here and there and then once identified they were either donated, there preferred way to honour the glory of god,  or bought by a Pope who happened to be collecting them at the time. Rooms upon rooms, galleries upon galleries are lined with these amazing artifacts.