That's the back side of Palomar. It sounds like trail or fire road. If you're on a road bike, I suggest parking at Harrah's Rincon and going one mile east on Rincon Rd, turn right on Hwy 76 for 7-8 miles and veer left at South Grade Rd. There's another 7 1/2 miles of climbing until you come to a store. You can turn around there or go another 5 miles to the observatory.

I parked there on New Years Day, rode through the orange groves on 76 and went up a dirt road called Nate Harrison Grade. I don't have a computer but someone told me its 10 miles at 10%. I rode a road bike with a 26/32 low gear. I only saw one other guy on the route.

Go to a cycling GPS site and type in Palomar, Sunrise Highway, Mt. Laguna, Couser Canyon, Rice Canyon or De Luz.