What is it?
Sabre® defines the data returned by the Multi-Airport City Lookup and Airports at Cities Lookup (or MAC) supplemental APIs, including the unique MAC codes, the corresponding city names, and the mapping of the major airports to each city. A metropolitan city may have more airports than we mapped to a city's MAC code because our APIs retrieve the airports that we support.
You could use this API to retrieve data for multiple major airports, as opposed to data for a single airport code. Simply call an air shopping or intelligence API of interest multiple times for each MAC airport code
How to use?
Multi-Airport City Lookup API
To get a list of city codes that are served by more than one airport, use the Multi-Airport City Lookup API. These multi-airport city (MAC) codes can be used with applicable REST APIs.
Example: Within the Destination Finder API, to search for the lead fares from DFW to any airport associated with New York City, use "DFW" for origin and "NYC" for destination. The response will include the lowest fare and lowest nonstop fare. The lowest fare will be from DFW to any one of the airports that belong to NYC, e.g., DFW to LGA. The lowest nonstop fare will be from DFW to any one of the airports that belong to NYC, but may not be the same airport associated with the lowest fare, e.g., DFW to JFK.