One of the tallest office buildings on this pre-war street became the heart of Polish Radio for a decade.

The radio station provided broadcasts for almost the entire country, with a super-charged 120kW transmitter – the most powerful in Europe when constructed – broadcasting from Raszyn, just outside Warsaw.

The building on Zielna Street has another history though. It was at this address that the Polish Communist Workers' Party was founded soon after the country regained independence in 1918, although it soon became outlawed…

Further reading on Culture.pl:

After World War II, Polish Radio provided a certain amount of artistic freedom with the creation of the legendary Polish Radio Experimental Studio:

• The Future Sound of Warsaw: An Introduction to PRES
• The Musical Milestones of the Polish Radio Experimental Studio

With thanks to:

• The Polish National Digital Archive, for providing Polish Radio archival recordings relating to the outbreak of World War II on 1st September 1939 (Ref: 33-P-571)
• Wojciech Oleksiak, the lead producer of sister podcast Stories From The Eastern West, for providing the voice of the radio announcer.
• Alicja Baczyńska, your audio guide, for help with acoustic mapping throughout the Unseen project.