Which major European city was liberated for the first time by local military units on April 25, 1945, before the arrival of the Allies?

Milan was the first major European city to be liberated by its own people during World War II. Italian partisans launched a general insurrection against the remaining German and Fascist forces and took control of the city before Allied troops arrived. This was the collapse of Mussolini's regime. Today, 25 April is celebrated in Italy as Liberation Day.

https://en.wikipedia.org/wiki/Liberation_Day_(Italy)