The Albergo Regina was a luxurious hotel built at the end of the 19th century in an aristocratic palace on Via dei Librai, not far from an old tavern opened in the 16th century in the old Rebecchino district. Between 10 and 12 September 1943, the hotel was occupied by the Waffen SS Adolf Hitler division.

The building was then requisitioned on 13 September, surrounded by barbed wire barriers and illuminated by powerful photoelectric cells. The headquarters of the Sicherheitspolizei (SIPO-SD, Security Police), which comprised the Gestapo (political police), the Kripo (criminal police), and the Sicherheitsdienst (SS Security service), were established here. Office IV B4, in charge of anti-Jewish persecution, was also located here.

The interregional command was entrusted to Colonel Walter Rauff, the inventor of the Gaswagen, the death trucks that gassed thousands of Jewish people in Eastern Europe. The interprovincial command fell to Captain Theodor Saevecke, head of the Aussenkommando in Milan (AK Mailand), who coordinated the anti-partisan repression.

The security cells were on the top floor, where the victims were subjected to lengthy interrogations and torture, then sent to San Vittore prison and from there in many cases to Binario 21 at Central Station, where they were deported. Many protagonists of the Milanese Resistance, such as Angelo Scotti, Aldo Rovelli, Roby Lepetit, Jusuf Roberto Mandel, and Don Giovanni Barbareschi passed through here. Ferruccio Parri, a main player of the Resistance and deputy commander of the Corpo Volontari della Libertà, who was accidentally arrested in January 1945, was also taken there.

It was also here that executioners such as Luca Ostèria, alias Dr. Luca Modesti, notorious OVRA agent, hung out. General Rodolfo Graziani was also sent here in April, .

On 27 April 1945, OSS (Office of Strategic Services) Captain Emil Daddario took possession of the building. The SS, held at gunpoint by the partisans, left Hotel Regina on the 30 April in a scene captured by the cameras of the US Fifth Army.

Today, Hotel Regina no longer exists, but a commemorative plaque has been placed on the walls of the building, now used as offices, in front of which the town ceremonies are usually held on 27 January.