From Airline Mogul
Note: The term "focus city" is interchangeable with "hub" or "bases".
Focus cities are the cities you can create routes out of. All worlds will have designated numbers of allowed domestic and foreign focus cities. A domestic focus city is any airport within the continent of your first focus city. For example, if your initial focus city is London-Heathrow, you a free to open another domestic focus city anywhere in Europe.
Some worlds may allow for foreign focus cities. That simply means any airport outside your initial continent. Please remember: every foreign focus city you open counts as two domestic focus cities.
For example, if the world has a 7 Focus Cities listing, that means you are allowed any combination of the following:
- Up to 7 domestic focus cities
- Up to 5 domestic focus cities and 1 foreign focus city
- Up to 3 domestic focus cities and 2 foreign focus cities
Check the Create Base page for further information on this subject.
In order to make the game more balanced, there are some slight geographical discrepancies that one should be aware of.
- Mexico, Caribbean nations, Bermuda, and other Central American countries are all classified as its own continent: Central America
- Turkey is classified as the Middle East