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Re: Longest Straight Line Paths on Water or Land on the Earth
From: Alexandre Eremenko
Date: 2018 Apr 23, 20:21 +0000

Without any algorithm, or complicated science it seems easy to guess that the 
longest path on water will go
from the North pole through the Bering strait to Antarctida.

Alex.

I'm going to make the assumption that by straight line they mean great circle.

By water I'm going to say that's the longest one that can be determined by Visual Inspection is:

A] Trondheim, North pole, Bering strait, Ross Ice shelf.  Lets say that's about halfway around or a bit more.

Using a cardboard cutout and my 12" globe there are a couple others that might work:

B]  PEI/NewFoundland, Gambia, Wilkesland, Tasmania, Alaska

Or the tough ones:

C]Sea of Okhotsk, Drake Passage/Antartic Pennisula, Gabon or thereabouts.

D] Alaska/BC,  Banda Sea,  Enderby land, Brazil.  The problem with this one is finding and appropriate GC route thru the Indonesian islands around the Banda Sea.

My bet is B] or some thing similar being the longes, 3/4 or more RTW..