At sign post 19, you'll see a sign that says "The Wall". You may say to yourself, "What a peculiar sign - what does it mean?". You'll soon find out.
The Wall, although doubletrack and not technical, will test your will. It will take you out of the valley in the most direct route, which in and of itself isn't the most difficult part. You'll feel like you are pedaling in quicksand as this is a trail that is frequented by equestrian riders. Dodge the paddies and good luck!