When I took this photo on a sunny spring morning I was trying to get La Scala from the same angle as in a famous painting by Angelo Inganni from the year 1852.
At that time the opera house was in a narrow street because the square, Piazza della Scala, was not created until several years later. Of course there were no tram tracks or overhead wires in those days, and no traffic lights.
Actually Inganni did at least two such paintings from slightly different angles, each with a two-horse carriage going off in different directions.

One of Inganni’s paintings from 1852
Here’s what one of the Inganni paintings looks like. In another version I have seen, there are two little boys scuffling in the foreground and the two-horse carriage is veering off to the left (our left, that is; their right).

La Scala as seen from the square in 2008
Here’s the front of La Scala as seen from the square, with one of the old-fashioned orange trams going by.

New ellipsis and rectangular stage tower
When the Teatro alla Scala was closed for restructuring at the beginning of 2002 they didn’t exactly tell the general public what they were planning to do.
About a year later there was a huge outcry when someone discovered from an aerial photograph that there was nothing but a huge hole where the historic 18th century stage used to be. This is when the management came out with the truth of the matter, which was that the old impractical stage was being replaced by brand new a state-of-the-art high-tech 21st century stage and backstage with all the latest machinery, so they could make scene changes without having hundreds of stage hands lugging things around.
When the restructuring was finished at the end of 2004 there were two very visible new elements sticking out from behind the historical façade.
On the left in the above photo is an ellipsis which contains among other things the dressing rooms for the singers, dancers, technicians, orchestra and chorus. On the right is a new rectangular stage tower which contains all the new stage machinery as well as rehearsal halls for the chorus, orchestra and ballet company.

Façade at night with ellipsis and stage tower
In this nighttime photo of the façade you can see the rows of lights that have been placed in the rectangular stage tower.

Ellipsis and stage tower from the cathedral roof
Here are the new ellipsis and stage tower as seen from the roof of the cathedral. The glass dome in the foreground is the roof of the Galleria Vittorio Emanuele II.
http://www.teatroallascala.org/en/
My photos in this post are from 2008. I revised the text in 2018.
Next: Prima delle Prime at La Scala.