From there it's a fun single track climb for 8 miles and slim the way you'll run into different spots for a great scenic view. Follower trail all the way up until you run right into Glendora Mountain road again. You can keep going past the road or head back down the same way. There are some hikers/runners mostly in the weenkends. Trail is good, a little rutted at times butterfly clear and very rideable. Fun climb, gear views.
From 210 fway in glendora off Lone hill avenue: Head north past 210 fwy north to foothill blvd, then turn left. Head west and turn right on Valley Center north. Go up to e.. Sierra Madre Ave. and turn left, then and immediate right on Glendora Mountain road. Follow the road up and when you just pass big Dalton road you will find a gravel/turn-out type unmarked parking lot on the left. You can park here and ride up Glendora Moutain road to trail head, or keep driving and park at the first sharp turn (there is a smaller unmarked turnout to parking lot On thr right. Trail head is just past that spot in the right. There is a sign and a white gate. Follow theriver bed trail until you get to the Munroe truck trail. it's not marked but its obvious.
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