From the top of the Lower Holy Jim Trail
, continue southeast. For the first 1.7 miles, it's a bit of up and down and the trail is mostly broken down sandstone. At that 1.7 mile mark, you'll see the Indian Truck Trail
start off to the left and head down to the Corona area. This is also where "The Wall" begins. The next mile averages 10% grade but the challenge of it comes from the loose gravel. It can be a challenge to clear if you don't pick a good line. Best to ride this after a rain when things will be tamped down. Add another mile after the gravel and you'll get to some downhill. You're past the toughest part.
At about 4.7 miles from the top of Lower Holy Jim Trail
, there will be a clearing with a wide 90+* left turn. Over the green guard bar on the right here is the beginning of the West Horsethief Trail.
Continue on, rolling up/down until your last push up to the clearing at the top of the Trabuco Trail.