For day use this park is a wonderful way to get out of the city without having to drive. El Moro canyon is a great hike, although a few sections are a little steep.
I was less impressed by Deer Canyon Campground. According to the ranger there were 5 sites there, but it was more like two sites with five picnic tables (and a good helping of poison_oak). The evening was beautiful with a fabulous sunset and lots of cute critters (bunnies, etc.). The morning, however, included about 30 mountain bikers riding right through the campsite and about half as many hikers, which made breakfast a little crowded.
Also, if you are hiking towards the back of the park, watch your step. Rattlesnake is not just the name of one of the trails.
Pros: Very beautiful, great hikes, getting out of LA without driving
Cons: Lots of company, Snakes
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