Trailhead for Nannie Ridge Loop Trail is located here. Parking for the overnight hikers is very limited and Northwest Forest Pass is required. Get there early. We squeezed into the last spot at 7am very tightly, in our Toyota FJ, right next to the shitters. The Nannie Ridge trail up to the peak is moderately strenuous as you get all of your elevation gain at the start. Continue upward and when you begin to level out and see sky don't miss the peak trail on the left up to Nannie Peak. It's about a half mile or so up to the remnants of the old fire lookout. Once down and back on the loop trail it's all gravy to Sheep Lake. Camp there for the night. Several spots to choose from. Warning: mosquitoes were VERY abundant but easily repelled with DEET 98% and netting. Enjoy a swim, the sunset and a very starry night sky. The rest of the loop awaits you the next morning. About 100 yards past Sheep Lake is the trail connection to the Pacific Crest Trail. Take a right to go south and continue on the loop. Easy walking for the next several miles and constant views of Mt. Adams. Where the PCT intersects with the Walupt Lake Trail is a good spot to hydrate, adjust packs, have lunch and get ready for the home stretch back to Walupt Lake campground. From here, you'll lose 1000 feet in elevation down into a drainage basin. A good stretch of trail was a rocky, washed out series of messy switchbacks along Walupt Creek. Easily the worst section of the loop. At the bottom you'll enjoy a nearly flat walk through the forest next to the lake and back to the parking lot. Happy hiking. Map distance is about 15 miles. My final pedometer reading said 24 miles. Go figure.