Which city is represented by the airport code DEN?

The airport code DEN represents Denver, Colorado, which is home to Denver International Airport. This airport is one of the busiest in the United States and serves as a major hub for both domestic and international flights. Each airport in the United States is assigned a three-letter code by the Federal Aviation Administration (FAA), and DEN is the designated code for Denver International Airport, reflecting its city's name.

Understanding airport codes is crucial for various industries, especially in travel and logistics, as they help in identifying locations quickly and efficiently. The other options provided do have their own airport codes – for instance, Detroit is represented by DTW, Des Moines by DSM, and Dublin by DUB – but none of these match the DEN code, which is specific to Denver. This highlights the importance of familiarity with airport codes in navigating air travel.