Standard route: ~70 miles, ~6,000ft. Express route: ~50 miles, ~4,000ft.
**UPDATE** NEW VENUE: The start/finish location is Mercey Hot Springs, 62964 Little Panoche Rd, Firebaugh, CA 93622 Info here: http://www.merceyhotsprings.com/
On a clear day, you can see across the Central Valley to the horizon which is wall-to-wall snow-capped Sierra mountains. The other direction, you’re looking into the old New Idria quicksilver (mercury) mine and the San Benito Wilderness. All around you will be arid, treeless desert in the rain shadow of a mountain range. You didn’t know that actual desert came all the way up to just 2h 30m from San Francisco now, did you? Double-track gravel road for miles and miles and zero cars for hours.
Bring low gears and 40mm tires for this one, and make sure your brakes are in top order as well (listen to me now and believe me later!). There are rollers that are like natural X-Games giant vert ramp drop-ins. 100′, 200′ and larger g-out dips await you, several in a row. The full route has a few short hike-a-bike pitches too (100′ or less) if you are not ready for them, but going the other way it drops 1,000′ in one mile (for comparison, Braille Trail at Soquel Demo Forest in Santa Cruz drops about 1,000′ in a mile as well…)