Retenzija is located in the southeastern section of urban Zemun, on the border with the municipality of Novi Beograd.
It borders the neighborhoods of Donji Grad on the north, Zemunski Kej on the east and Paviljoni on the west.
It is bounded by the Boulevards of Mihajlo Pupin (west) and Nikola Tesla (east) and the streets of Prve pruge (north) and Džona Kenedija (south).
Retenzija corresponds to the area of Blok 9b, one of 72 residential blocks drafted during the construction of Novi Beograd, which began in 1948.
Retenzija is a residential area with a population of 9,344 (local community or mesna zajednica Prve pruge, administrative municipal subdivision).