Great question - CPH to KNX just means Kastrup Copenhagen Airport to Kununurra Airport. Now you’ll know what these unique codes when you look for flights! This flight route has multiple associated airports, so we think it might be helpful to learn the name and codes of them as well. They are Madrid Barajas Airport (MAD), Barcelona-El Prat Airport (BCN), Amsterdam Schiphol Airport (AMS), Lisbon Humberto Delgado Airport (LIS), Frankfurt am Main Airport (FRA).