Beautiful and secluded!
I love Zaleski and have returned multiple times. These campgrounds and hiking trails are my go-to for a weekend backpacking trip. Rarely have I seen other hikers on the same trails but we always meet people at camp. The terrain has many climbs and descents and takes you along ridges, through valleys, and along forest floors.
All of the campsites have multiple areas for different hikers and each is relatively secluded from the others so you can be by yourself. All campsites have an outhouse and potable water all within easy reach from all camping areas. I've never felt cramped by other campers and we've always had a great spot to make a fire, hang our food, and put up a line for our clothes to dry on (if needed).