Global airlines are governed by strict 'freedoms of the air' dating back 80 years. They've created some funky routes.

• Global airlines are governed by nine "freedoms of the air," drafted 80 years ago in 1944.
• These dictate how airlines can operate in foreign nations, with some more complicated than others.
• The fifth freedom can give airlines a competitive edge and help capitalize on demand.

Over the past 100 years of shuttling people around the globe in metal flying machines, the world's aviation network has grown into a vast web of intersecting routes that connect nearly every corner of the globe.