Make the rule “Industry” a subrule of the rule “Population”.

Add a new subrule “Specialties” to the rule “Population” and give it the following text:

The following types of Zones are Specialty Zones: Fortress, Harbor, Mining, Tourism, and University.

A City Architect whose City has no Specialty Zones but more Population than total Zones may add a Specialty Zone of any type to their City as a daily action, so long as at most one other City is in the same Region and has the same Specialty Zone.

If a City has two or more types of Specialty Zone, it may not gain a Specialty Zone of a type it does not already have.