This Rock requires a bit of a hike, but is well worth it for its pleasant shaded atmosphere, and the number of moderate slab routes (5.8-5.11mumble) it offers. All of the routes can be relatively easily top roped, and most are bolted.
Getting There
Approach Time: 10 - 20 minutes.
Start from the Castle Rock State Park parking lot, and start down the Saratoga Gap trail (the entrance is about 15 yards to the left of the latrine) for about 200 yards to a side trail which splits off to the left up the hill at a sign post.
Follow the left trail up the hill through a number of switchbacks until you see a the first smaller unmarked trail to the right (there is a log along the right side of the main trail which separates it from the smaller trail and a sign informing you that this is not 'the' trail.) Take this right trail, and if you see a series of nice looking boulders on your left (the largest with a small cavelike formation called The Graveyard Boulders and Pyramid Rock) you have gone too far.
Take the climbers trail for about 100 yards to a moderate clearing (this used to be part of an old road.) There are two small trails (ok, they look more like goat paths than trails) on the far side of the clearing. One leads up and to the right of Chew Tooth Rock, while the other leads down directly to the top of The Underworld. Top ropes for most of the climbs here can be set up from one of 2 sets of bolts accessable from here.
The Classics
Mountain Project's determination of some of the classic, most popular, highest rated routes for Underworld, The:
One minor inconvienence surrounding the Underworld is that almost all climbs share the same anchors atop the rock. That means if another party is there, you've just done the hike for nothing... unless you're creative.
Equalize an anchor with a 6' sling from the tree branch atop the rock and the last bolt of Underpass. With this anchor (as long as you stay right of the other party) you can toprope or lead Poop Shoot and anything right of there.
By Bryan Howell From: San Francisco, CA Apr 21, 2008
Is the anchor situation still the same now, in good ol' 2008? Anyone been there recently who can shed some light on this?