Young communist pioneers meeting in Warsaw.
Feliks Dzierżyński Square in Warsaw
with a trumpet
Zlot młodych przodowników budowniczych Polski ludowej = Meeting of young building activists of the Polish People.
The Polish flag shows 20/22 VII, which represents the date of 20-22 July 1952 when the Constitution of the People's Republic of Poland was proclaimed.
Warszawa 1952 = Warsaw 1952.
The constitution of 1952