Park as for Practice Rock and hike 100 feet up the road to a faint trail. Look for an old stone foundation wall and angle up and right to a large ledge below the Cornerstone cliff (5 minutes). One can also approach from the Bowling Alley by following the trail that angles uphill and north/west along the Tungsten Mine Shaft Cliff, angle downhill towards a gully and scramble up onto the ledge below the Cornerstone cliff (10 minutes).
Mountain Project's determination of some of the classic, most popular, highest rated routes for The Cornerstone:
The leftmost route on the Cornerstone. The first bolt is just below and right of the shrub atop a short right-facing crack. The climb can be 5.9 by moving left by the 3rd and 4th bolts (you can still clip them if you're leading)....[more]Browse More Classics in CO
Actually, I'm not Dan but his cool chick, Jenelle. Many thanks to whoever repaired the chopped hangers at The Cornerstone. It's really a fine solid rock with 6 good routes for their grades. All can be done in a short period of time, even on your lunch break. The only slip in June - Aug. is that it is extremely hot. I recommend after 5pm or early morning. This is excellent choice for winter climbing and great for a mixed party of beginner and advanced climbers.
The routes here are fun enough, but at times it's tough to know exactly where the intended climbing lines are in relation to the bolts. It's very easy to find yourself wondering if you're using a hold that's "supposed to be" for a neighboring route. Still, a decent place to go to get a little climbing in.