Drive through the tunnel towards Wawona, park immediately after the tunnel on your right using the semi-large parking area that sports a payphone.
Walk back through the tunnel on the sidewalk towards the overlook.
You can squeeze through the blowhole gate but beware the belay area can often be wet. Consider anchoring to the gate as a lead fall would likely pull not only the leader but the belayer over the edge. Livable fall, but uncomfortable just the same.
Opposite the gate (climber's right) is a small ledge with a fixed anchor. Maybe for spectators? There are no routes to speak of over there.
Just left of the blowhole is a 5.9 a few 10's and further left even some 11's. A few routes can go 2 pitches but we've only done them as single pitch. Seems like we always bring a 70m.
Pretty well bolted with good anchors. Most routes start and the small platform in front of the gate and traverse over to the routes.
Ken Yager is a good resource and the man with the vision, try emailing him direct from using the ST.
They're good, I've been there numerous times in the heat of the summer. A shady destination when it's 105+ on the valley floor.
Seems it would be cold this time of year.
p.s. Russ just told me that's a lot of typing to say "walk the tunnel 120 yards"
I remember you have to traverse out to the start of the climbs on some exposed and a bit dicey ground;.....I think we roped up just to get to the climbs......It's not a place to take kids, dogs, grandma, or the n00bs, but I remember the climbs being very good. ....I also think it's an area where you won't see the crowds of Church Bowl, Manure Pile, or Swan Slab...Thar she blows....