This is a great two-hour roundtrip in the Chino Hills State Park. The box is placed up the trail right on the border between Orange and San Bernadino Counties. The fire road can be walked in walking shoes, but because it gets washed out, I still recommend hiking boots or something with a little ankle support.
The trailhead is located on Blue Gum Drive, near Rim Crest Drive. The residents don't like you parking near the trail head, so park on Rim Crest and just go up the hill until you see the trailhead sign at the cul-de-sac.
The contents have changed quite a bit in 12 years. I would love to see what's there now. Feel free to email me an updated photo.
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