Our old AF base north of Edmonton Alberta (CFB Namao), used to boast a 14000+ ft main runway. It was originally built as a dispersal base for flushing SAC a/c north (and thus closer to the Sov Union). For a long time, it held the title of the longest 'paved' runway in North America. When we shut it down and the Army moved in, they cut up most of the runway and the remainder was used as foundations for new tank sheds and running areas for driver training.
Ironically, when we had the base, all we flew there were Hercs, Twin Otters and Hueys. Not much need for that long a runway...
Boomboy64