OverviewJam Crack is a great intro into Yosemite crack climbing. The first pitch is easy to protect and has solid hand jamming. The second pitch gets progressively thinner with a very fun fingers crux. Expect lines for this climb. Bummer and Lazy Bum, 10c and 10d respectively, can be toproped from the top of the first pitch.
Getting ThereLocated at Sunnyside Bench. Park for Lower Yosemite Fall and walk on the paved trail to the bridge at the base of the Fall. From there head east for 100 yards until you get near the rock wall. Look for a climbers' trail heading right to the base of the climb.
Route DescriptionPitch 1: 5.7, 60 feet. Move up sustained hands to a ledge. Traverse left to a bolt anchor or build an anchor in the crack to the right if occupied. Make sure to set a directional at the ledge for your follower.
Pitch 2: 5.9, 80 feet. Move up from the ledge via a slightly awkward move to gain the crack. The crack narrows from good hands to the fingers crux. Belay from the bolt and chain anchor.
Descent: Two single 60 meter rope rappels get you back to the ground and start of the climb.