Denver International Airport stands out not only for its staggering size—nearly three times larger than San Francisco and double Manhattan—but also for its ingenious design and strategic importance. Built to replace the overcrowded Stapleton Airport,

Denver International Airport (DEN) is experiencing major delays and diversions due to thunderstorms. Arriving flights are delayed by an average of 3 hours and 9 minutes, with delays reaching up to 8 hours and 11 minutes.

The frequency outage meant that as many as 20 pilots were unable to reach air traffic controllers as they descended into Denver International Airport on Monday afternoon, ABC7 reported, citing sources. A controller eventually made contact with one aircraft on a “guard line,” which is typically only used when a pilot is in distress.

Denver International Airport CEO Phil Washington is again being pressed for answers about costly business class tickets that he approved for his executive staff.

Newark has been plagued by numerous issues for weeks. On Saturday, it saw the second most delays in the country.