Question

On a trip to a historical site your friend is writing his name on the structural

Answer 1

<<The question is incomplete. However, it is has been answered on the assumption that the question is how I would react to what my friend is doing.>>

I will tell my friend that what he is doing is quite wrong and that such an action should not be done. The structure present at the historical site is a public property and is intended for everyone to admire. I will also make him understand that writing on such structures is equivalent to destroying it. As the structure does not below him, he has no right to right his name or scratch on the same.