Talk: Trade Route (Civ6)

Added a paragraph about Trade Route duration. Sources:

https://www.reddit.com/r/civ/comments/5aqzov/trade_route_explanation_questions_and_how_close/d9is1ou/

https://www.reddit.com/r/civ/comments/5aqzov/trade_route_explanation_questions_and_how_close/d9jjyz6/

If this has changed in recent patches or can be disprooved, please correct accordingly.

89.13.22.135 02:09, March 6, 2018 (UTC)