Rulebookp. 58
Farthest
When a rule or effect refers to the farthest hex, feature, or token, it means the route to that feature or token that consists of the most hexes between that feature and the component being measured to (or from).
When a rule or effect refers to the farthest hex, feature, or token, it means the route to that feature or token that consists of the most hexes between that feature and the component being measured to (or from).