Grantanow
It's quite interesting that many historic buildings and monuments have graffiti carved on them from long ago. Roman soldiers did it. The statues of Ramses II at Abu Simbal have graffiti from various periods including, I think, the Victorian. Buildings at Pompeii have contemporaneous ones. I saw some graffiti in the German parliament dating from the end of WW2 which had been preserved.
Ironic really, isn't it, that we tend to cherish old grafitti, but condemn the modern.
OTOH, with so many thousands of visitors to ancient (and not so ancient) monuments these days, where in the past the number of sightseers would have been far fewer, I suppose we can't have them all leaving their mark on them...