I am assuming the reference is through the Green River Golf Course... good luck finding another way in. I have been trying for years. All entrances from that east side of Chino is illegal (I wrote the park service and asked!). Kindof sucks since I like to go in that way! I have heard, but not found an illegal trail that starts east of the mobile home park and golf course... maybe something worth exploring? If you find it let me know.
Frankly I still ride in through Green River CG and no one has yet to say anything to me.
The legal entrance, by the way is off the 71 in Chino Hills. There is an actual ranger station there.
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Private docent led mountain bike rides through Limestone Canyon. Go to
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