If Aperol Spritz and a great view of the Duomo is what you're looking for, then Terrazza Aperol is the place for you. The view over the Duomo is incredible and the Aperol Spritz here is delicious.

I'd recommend it for sunny days, and of course make sure to get a table outside. The vibe is great too!

Prices are not cheap at all, one Aperol Spritz is €15 (standard in Milan is €8), but it's one of those experiences to do at least once, so if you're visiting Milan for a few days, I'd certainly recommend it.