Definitely a moderate to hard trail, more on the hard side given the elevation and distance . The entire loop is exactly 9.9miles (starting and ending at the entrance parking lot ) and we hiked it clockwise. The climb to the top is ~4.5 miles and elevation gain is around 400ft/mile and is a great workout (going Counterclockwise results in a relatively shallow climb but a steep descent which is very hard on the knees). Great Panoramic Views of the valley provide some respite in the climb. Bring lots of water. Overall, a great workout and an enjoyable hike