Frontier Airlines Cancels 19 Routes From Denver In 2026: See Full List & Map Now

For many years, Denver International Airport (DEN) was overwhelmingly Frontier Airlines’ most-served airport. This was until the carrier launched its pan-US operation focused on point-to-point routes. When seats for sale are considered, DEN lost the throne to Hartsfield-Jackson Atlanta International Airport(ATL) this year, despite multiple routes being cut recently.