Option 1: You can go up through the Cottons and Brittons (Ferns), turning left. You'll meet up pretty soon with the Great Western Road (after some ducking and diving under branches).
Option 2: Head back to the Great Western Road.
Keep going up the Great Western Road. Eventually, you'll spy a great stone staircase. And at the top of the staircase you'll see a mysterious stake in the ground with some arrows on it.
Multiply the number of steps with the number of arrows to get the next password..