Southwest Airlines, the largest carrier in the U.S. by passengers, operates approximately 4,000 daily flights across its network. From Denver International Airport (DEN), the airline has identified its top 10 busiest routes, as outlined by Cirium, an aviation analytics firm.
Southwest, which has an exclusively Boeing 737 fleet, flies about 140 million passengers annually with the help of 72,000 employees. This data reveals a pattern of high-frequency flights connecting Denver with various U.S. cities.
Starting with Houston (HOU), the airline conducts flights from one of its earliest destinations since its founding in 1971. This route is often used for connecting flights. Flights to St. Louis (STL) and Salt Lake City (SLC) are also popular, with the latter being the shortest at 391 miles.