When travelling, the Passenger will travel along lines which the players have built, and also move along empty track spaces, if necessary. The Passenger will choose how to move according to the following rules:
1) The Passenger will choose the route that involves the least amount of empty track spaces;
2) If two or more routes involve the same number of empty track spaces, the Passenger will choose the route with the fewest (or even no) lines.
- When moving the number of Track tokens making up a line doesn't matter, only the number of different lines.
3) If two or more routes involve the same number of empty track spaces and the same number of lines, the player moving the Passenger decides which route is taken.
To sum up - the Passenger doesn't line to walk (use empty track spaces) and the lenght of the lines they use doesn't matter, as long as they have to make the least amount of transfers between different line.
Because the length of the lines the Passenger chooses to use doesn't matter, it means that the Passenger won't always take the shortest route! This is important to remember.