Aside from the parts scattered in and around the immediate vicinity, I've recovered pieces from trees, the roof of ticket offices and platform canopies, overhead lines and even neighbouring gardens. It isn't the sort of thing you would want your kids to find, or for the cat to bring in through...
Should you ever be unfortunate enough to be asked to clear up after a person has been struck by a train you will appreciate that it is neither a quick nor easy job for any of the agencies involved.
I've been done several and no matter what people may think, we don't sit about drinking tea.