Where can I find the base of polygons of the cities of the CIS countries?

Question

PHP

An example to understand the essence of the issue
https://www.google.com.ua/maps/
When we enter a city/village, it highlights it on the map.
For example Boryspil and its region

That is, I need polygons not only of cities but also of their regions.
Please help, where can I get such a base? Mb someone faced such a problem.
Thank you!

Answer 1

I'm not sure if there are polygons up to cities, but it's worth a look.