A couple different solutions, however both start at a small crimp flake at chest height. The climb is short but sweet and a must try if you make it out to rancho penasquitos

Either work up left to work with a gaston crimp or fire big to reach the ledge/rail that connects with the lip.

Hangnail Left

Lucah Thumb

Hangnail Right

Start with right hand on the arete and the left hand in a large flat undercling. Stand up and bump the right hand on the arete until you can use a toe hook to get your left hand up and make moves to the top of the boulder.

Start on the left side of the face but work through a series of sidepulls facing the wrong way to finish on the right.

Description

Protection

Routes in Thumb Boulder