This list contains the airport codes of IATA airport code and ICAO airport code together with country code and region name supported in IP2Location geolocation database.
I originally wrote a C program to check for distances between airports around the world, and I found some airports with possible duplicate entries: https://www.mapcustomizer.com/map/Duplicates
(Accidentally typed shift-enter into the browser, because I still need to write the description.)