I spent the president's day holiday hiking in Black Star Canyon, a wilderness area nearby enough that it's barely outside Irvine and remote enough that in the upper part of the falls trail (where you're basically scrambling up a creek instead of hiking along a trail) there's no sign of civilization to be seen except for the other hikers, airplanes overhead, and occasional painted rocks.

Oak tree in Black Star Canyon, Orange County, California

( More photos of Black Star Canyon )