I learned yesterday that St. Petersburg (Russia) airport is LED, which are letters found in its old name: Leningrad.

ABIA is the abbreviation/acronym of the proper name of Austin's airport, Austin–Bergstrom International Airport, but the IATA code actually is AUS. When I search for a flight, I use AUS as the search term, when I search for the airport on Google Maps I use ABIA, and when I send an informal email and abbreviate Austin is write ATX.

The previous Austin airport (Mueller, closed 1999, now a planned community) also had an IATA code of AUS. They did a single day cutover from the old to new airport, so they were never both in commercial use at the same time (Bergstrom was an Air Force base for similar years as Mueller).