The Great Wall isn't in the main Photographer's Peak area, but it is close, and uses the same trailhead. There is 7 routes that I know of on the wall. The climbing is good, but the routes are short and not as good as those on Photographer's Peak.

Drive to the Photographer's Peak parking area described under the area directions. The Great Wall is found by getting on the old dirt road that leads east from the parking area. This road quickly turns to a singletrack, and then soon is so overgrown that it disappears. At this point, continue walking through the overgrown treeless meadow, heading more or less in a straight path away from the car. Then you will cross Trail #4, and Great Wall is just up the hill. Walk up to its base through dense trees. Then about 20 feet of easy scrambling is required to get to a shelf at the base of the routes.