A conversation with dtcwee sparked the following analysis of how the cultural (and economic?) global midpoint has shifted over the last two milennia: http://dtcwee.blogspot.com.au/2016/04/the-history-of-center-of-world.html

Definitely worth a look, if you don’t mind your Western-centric complacency being thoroughly disturbed.

Don’t forget folks, from 330AD the capital of the Roman Empire was Constantinople…