Which airport code refers to Grand Rapids, MI?

The airport code that refers to Grand Rapids, MI, is indeed GRR. This code is part of the International Air Transport Association (IATA) airport code system, which assigns unique three-letter codes to airports worldwide to facilitate air travel and communications in the aviation industry. GRR is specifically used for Gerald R. Ford International Airport, the primary airport serving the Grand Rapids area.

The other codes are associated with different airports: GSP is the code for Greenville-Spartanburg International Airport in South Carolina, IAD refers to Washington Dulles International Airport in Virginia, and ICT is the code for Wichita Dwight D. Eisenhower National Airport in Kansas. Each of these airport codes serves a unique location, highlighting the importance of knowing the right codes in the context of air travel.