This area has the classic 5.9 thin crack "One Line, No Waiting"
Getting There
This area is located between El Segundo and Whitney Portal Buttress directly above the switchback of the Whitney Portal Road. Best approached from the Wood Road, as with Premier Buttress. 35 minutes.
The Classics
Mountain Project's determination of some of the classic, most popular, highest rated routes for Hairpin Wall:
The route seemed a little stiff for 5.9, more like easy 5.10. And it doesn't really need an 'R' qualifier. The protection and belay bolts on the first pitch (the best one) have been replaced. Should only get three stars.
The trail to this wall is nonexistant. Currently not worth the bushwhack to get there for the one route. There are at least two other new routes on this wall, information is unavailable though.
Go up the gully from the hairpin turn (same approach as El Segundo), stay in the gully until fairly high relative to the right side of the Hairpin Wall - then cut left to the wall. This approach is pretty open.
The other routes:
Take a Number 10a (r). Two pitches, left of One Line No Waiting.
BLD 11a, 1 pitch. Center of wall, obvious crack at start then face. Traverse from right to start of route.
Three's a Crowd 10b. Two pitches. Starts under the roof on the right side of the wall. Second pitch traverses left under roof. Cool tooth feature under the roof.
BLD (P1) and Three's a Crowd (P2) share an anchor. From that anchor it is possible to join One Line No Waiting.