This was my 3rd climb of Islip, and from a 3rd different way. I hiked up the Islip Ridge Trail from the lake area itself. At a switchback curving from south to north early on around 6100', I left the trail for a short cross-country walk (about 0.15 mi r/t) to the southwest to Bump 6130 with a sweet view of the San Gabriel Wilderness under the shade of pines and firs. I then returned to the trail and continued the warm, mostly sun exposed (with some shade from the open stands of pines and firs) slog along the very scenic ridge, with more views to the San Gabriel Wilderness to the west, the Crystal Lake basin below to the east, and Hawkins Ridge farther to the east. I made it to the summit where the roofless summit stone cabin was filled with several feet of snow, making the last bit a slippery slog over deep snow, but the summit itself was clear. I stayed for about 45 minutes, chatting with a boy scout group who came up 20 minutes after I made it. Then, avoiding the snow, I scrambled down the south slope to quickly rejoin the Islip Ridge Trail. I hiked down to a small saddle, and turned south off trail for a short, easy climb to a small summit about 7,620 ft in elevation. I returned to the trail, and soon, I then joined the Big Cienega Trail down alternating areas of lush pines, cedars, and firs, and chaparral laced with burnt snags to a road. I went on the road and followed it to check out Deer Flat Group Campground at 6,300'; I have never been to it previously on my Crystal Lake visits, and I enjoyed the large trees there. I followed the road which led to the lower Windy Gap Trail, which I followed through the Crystal Lake Campground. I hiked along Crystal Lake Road to the lake access road and to my car. Warm, tiring day but with awesome rejuvenating sights, sounds, and mountain air!! Beware, there are some areas of blowdowns on the Islip Ridge Trail after this winter's crazy storms. Elevation gain was about 2,800' on the round trip, with a slight gain back to my car along the lake access road.