The Galleria Vittorio Emanuele II - the grand glass-roofed mall--it's one of Milan's most…read morephotographed areas (other than the Duomo which is directly in front of it) and is very distinctive. Designed by architect Giuseppe Mengoni and opened in 1867, it contains a central octagonal space and dom made of glass - one of the most distinctive in the world!
Inside, you will find clothing stores (most designer) and a few places to eat. It gets very busy with people shopping, taking allot of photographs, and congratulating around a few points of interest such as the famous bulk mosaic--there is a little dance you can do to bring you good luck!
If you're interested, you can search for damage on the Galleria in WWII and they have rebuilt/restored it very well! Just outside the Galleria, you can also see the Opera House, more shopping, and even a monument or two in remembrance to the WWII resistance!