In 2008 a fragment of an ancient Roman equestrian statue was found among the remains of an ancient pavement during excavations. I'd guestimate it at about 1.5m square and from what I've read the assumption (not a certainty) is that it was once affixed to the arches of the Colosseum.

You can make out the centre of the horse and fragments of the rider. It may have been of an emperor, but it does have a touch of the Ozymandias-es about it.