From the rule book:

DELIVER GOODS CUBE - The active player may move one goods cube from one city to another city, thus delivering that cube to a destination. The goods cube must be moved along "complete links" to a city that is the same color as the cube being delivered.
The cube may move "a number of links" up to and including the engine level of the active player.....A cube MUST stop moving and be delivered as soon as it reaches a city of the same color.

My QUESTION
IS a "link" a (segment of track, aka one track tile hex), or is a "link" the "completed link" between two cities?


For example between Milwaukee and Chicago there are two "hex tiles" spaces. Does it require a level 2 engine to move a red cube from Milwaukee to Chicago or can this be accomplished with a level 1 engine??


Thanks
JP