This is the 6377th most frequent Polish word.
burmistrzów
"Mayors" (plural form).
The word "burmistrzów" is used here in the genitive plural to indicate possession or to specify the group of mayors being referred to.
Spotkałem się z kilkoma burmistrzów na wczorajszym zebraniu.
I met with several mayors at yesterday's meeting.
The term "burmistrzów" represents the genitive plural use, showing that the projects belong to or are created by mayors.
Rozmawiamy teraz o projektach przygotowanych przez różnych burmistrzów.
We are now discussing the projects prepared by various mayors.
Here, "burmistrzów" in the genitive plural form signifies belonging or association with "those mayors" whose work is being acknowledged.