off topic, places to visit in milan

next month we will be visiting milan for 3 days, my girlfriend was there 5 years ago, so nothing special to see or visit, but i want to make surprise for her, anyone know some beautiful romantic places that are not very well known?

and is expensive there ? i think i want to rent a car, and not travel everywhere with bus or train,

my pocket is quite small nowadays, but still want to do something nice

Milano is very expensive.
Very.
Navigli for nightlife.
Castello Sforzesco
Galleria Vittorio Emanuele II
Duomo
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