He's 27 and claims he didn't know how old they Colosseum is?! Bullshit. He's only apologizing because he got caught.
Agreed. What he actually didn't know was that there was a 15k euro fine and a five-year prison sentence.

Honestly, I think he should just get the fine and maybe some community service. It’s not like he did some terrible evil thing, he simply caused a tiny amount of damage to huge ancient structure.

Why should he lose 5 years of his life over something simple like this? Just give him a big fine that makes him regret it, and he won’t do it again.

I would give him 2 year probation/suspended sentence. Does not need to ruin his life but make the warning hella clear.