Originally Posted by sefrischling
The obvious to me is my home town with JFK - LGA - EWR (but EWR is in Jersey, so screw it).
San Francisco (sort of) SFO - OAK - SJC (you can see OAK from SFO and vise-versa).
San Francisco only has one airport. You could make the argument that OAK is a secondary airport serving the frater Oakland/SF region. SJC is in a different metro area so really would not be considered an airport for SF. SJC primarily serves the San Jose/Silicon Valley area as well as the Greater Santacruz and Monterey areas.