Ample parking and vault toilets can be found at Islip Saddle.
Just across the street from the parking lot, jump onto the Pacific Crest Trail here.
The trail meanders up a few switchbacks before assuming a gentle uphill grade.
About a mile into the hike, you'll come across a dirt road. Continue straight across.
Two miles in you'll pass Little Jimmy, a historic backcountry campground right off the PCT.
Fire rings and old-timey backcountry ovens dot the landscape at Little Jimmy.
Once you've passed the campground, continue heading south on the trail toward Windy Gap.
You'll pass right by Little Jimmy Spring, which is a perennial source of water. Be sure to treat it first!
Take a right at Windy Gap and head up the ridge toward Mount Islip.
Old-growth pine trees surround you in this alpine forest ecosystem.
The views at the top are incredible, with Palmdale on one side and Crystal Lake on the other!
An old cabin still remains at the summit, making a good windbreak or snack spot.