One of the places in Milan I most wanted to see and visit is the Duomo. It’s the largest marble structure in the world and took over 600 years to build. It is quite impressive and you can go inside and up as well either on foot or via elevator.
If you are going in the summer like I did , go up early in the morning otherwise it will be super hot. It was very hot already at 9am.
There is a museum of artifacts behind the Cathedral as well with beautiful stain glass and sculptures.
cocodiva 