What city is represented by the code DEN?

The city represented by the code DEN is Denver, Colorado. Airport codes, such as those used by Alaska Airlines, typically consist of three letters that are unique identifiers for airports. DEN is derived from the name of the city itself, where the major airport, Denver International Airport (DEN), serves as the primary gateway for domestic and international flights in the region. This aligns with standard airport code conventions, where the code often relates directly to the city's name, making it easier for travelers and airlines to identify locations quickly and efficiently. Other choices, while being valid city names and even home to airports, do not share the corresponding three-letter airport code with DEN.