I just got back Thursday with my 14 ft Teardrop Trailer. No problems at all. Just go slow driving in as the road is very twisty!
You can camp wherever you’d like in Angeles national forest as long as you have a current adventure pass displayed
Buckhorn is the type of Campground for tent camping, not trailers.
The only camping allowed in Buckhorn is in the campground. Most sites are small, can barely park 2 cars.
I know Buckhorn really doesn't have room for a big trailer maybe for a small Airstream but I don't think you can camp with a trailer you would have to find out Visitor Center or footrest services/Rangers.
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