My nephew is in Paris right now and will be in Madrid this weekend - he’s going to the Athleti/Osasuna game on Saturday.
While I’m sure he is/will be fine, I know this makes his mom/aunt (my wife) nervous.
We lived in Italy in 70’s. We saw a lot of Roma games and a lot of Lazio games, but my dad would never let us see them play each other (they shared Stadio Olympico). Derby games were known to be spirited..