...the front façade facing toward the city.
The original kernel was a gate on the ancient Roman walls around the city, protecting the city from invasion from without.
In the Middle Ages, under the Visconti family, it was enlarged, and became a military fortress, protecting the city from without, but also serving as a last resort to protect the Visconti (who still lived in the ducal palace next to the Duomo) from the Milanese. Decidedly a change.
In the meantime...those are my translations on the info panels scattered throughout the open grounds of the castle! They are still there after yea so many years. What a satisfaction.
Monday morning hugs to all,
P.S., Pooh on those who say, in error, that Milan is a gray industrial city with bad weather and nothing to see!