Sugarloaf seems to be a popular name for hills and mountains. GC.com lists at least 2 pages of caches with Sugarloaf in the title. As far as the bay area goes, there's a Sugarloaf in San Mateo County and one - this one - in Contra Costa county.
I recently visited the Contra Costa Sugarloaf and did the caches in the park. The hills were a beautiful green and I didn't even mind bushwacking back and forth over them. It wasn't easy finding the parking lot though, and I figured I would hide a cache to try to fix that.
Take Rudgear Road east to Young's Valley Road. Turn South and your GPS should tell you the rest.
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