Hi Chris,
I am sorry, but what is your question?
Because you mentioned OpenCitiesMap product, I recommend to move your question to OpenCitiesMap forum (when your question is a user one) or to Geospatial Programming forum (when the question is programming one).
Regards,
Jan
Bentley Accredited Developer: iTwin Platform - AssociateLabyrinth Technology | dev.notes() | cad.point