Longest straight line over water, without hitting land.
http://www.techtimes.com/articles/226599/20180501/what-s-the-longest-straight-path-on-earth-you-can-take-without-hitting-land.htm
http://www.techtimes.com/articles/226599/20180501/what-s-the-longest-straight-path-on-earth-you-can-take-without-hitting-land.htm