Location
Rubicon, like the classic Bird of Fire, makes the trip to Split Rocks more than worthwhile. From the Split Rock parking area follow the trail South towards Bird of Fire, which can be seen in the distance. As you walk in, the Rubicon Formation will appear to the left about halfway to the Isles in the Sky and Bird of Fire.
BETA
The route starts in a 2-3" crack, goes up about 20', and then traverses left across an easy horizontal until it reaches the beautiful finger crack which you follow to the top. Some parties belay at the end of the traverse. Others will use double ropes to avoid drag, and some will simply solo the start and traverse, belaying from the ground directly beneath the finger crack. A direct variation climbs straight to the finger crack up the unprotected face at about 5.11bR. The descent is by rappel from a bolted anchor.
Take a rack of cams and stoppers up to 3". The finger crack takes bigger nuts than you might think looking from the ground. You'll need some cams around 2" on top as the rap anchor is not positioned as a belay. Depending on how you ran your rope and pro going up, and how strong is your follower, it can be a good idea to pull the rope up through the gear and drop it back down in the clear to protect the start and traverse. With an anchor set well behind, you can adjust your position on top to provide a good belay all the way.
A single 50m rope makes the rap.
PS: I have seen rattlesnakes in the bushes at the base more than once in the spring.
History
This route was first climbed as an aid line in 1976 by John Bald and Hank Levine. Alan Bartlett mentions in his guide that this ascent began directly beneath the upper crack with a shoulder stand and hook moves! John Long and some friends TR'd the route free shortly thereafter. Then, in December 1978 John Lonne, Herb Laeger, Rich Smith and Eve Viga brought in the first free ascent.
John Lonne had a penchant for establishing burly routes. In 1976 he did the Banana Cracks. In '78 he did Morongo Man, which features an 11.d crack going 25 feet out a horizontal roof. When I met Lonne once at Stoney Point I was surprised. His clean cut appearance and perfect manners belied the stories I had heard about this rough and tumble man who would start a fight in a cowboy bar just for kicks. During those same years Herb Laeger, who has an eye for a good line, established numerous Josh classics including Run For Your Life (with Dave Houser and CHarles Cole) and Heart and Sole. Herb, who began climbing in the Gunks and Seneca, has been one of the most prolific first ascent climbers in California for 3 decades. Eve Viga, soon to become Eve Laeger, was one of the best women in climbing at the time. She and Vaino Kodas are the Estonians of the classic "Esto Power" on Power Dome at Courtright Reservoir.
Miscellaneous Info
You will notice two other routes on this face:
To the left of Rubicon is Mr. Swing, a 5.11c bolted route put up by Lavon Weighall and Chuck Davis in 1988. One can do the start of Mr. Swing and easily connect up to the Rubicon crack for a spicy variation with a 5.11 crux that is better protected than the regular direct start for Rubicon.
Sharing the start with Rubicon and then ascending the steep face directly above is Seizure, a 5.12c. First Ascent Kris Solem in 1988.