Very roughly, the westbounds tend to go further north than the eastbounds, due to common weather patterns. Not always the case of course. This is even more pronounced across the Pacific, where New York to Tokyo tends to head north, virtually over the North Pole, where returning they come across the Pacific and British Columbia.
Anadyr, in the Russian Far East, to Moscow, a domestic flight, can be routed westbound just a little further north than the Great Circle and pass over the North Pole itself.
I've done London to Miami over Prestwick and Newfoundland, and next trip direct, overhead Bermuda. I've also just once returned from SFO to London and never crossed Canada, overhead Chicago and we coasted out around Bangor ME.
Last edited by WHBM; 29th Jul 2018 at 01:25.