Canyons are inherently risky. Flash floods occur without notice on sunny days. Technical skills & surrounding topography knowledge required yet does not eliminate risk.
One Ugly Rock!
Dome Rock, sitting down on the southern end of the frontal foothills below The Mesa, is often mistaken for it's sister prominence, Prominent Point just a bit further south. There are numerous obvious differences: the most obvious being Prominent Point is taller and has a real trail over to it.
Dome Rock, standing high above Quiet Canyon has no easy trails. This will be an off trail trek. In fact, one of the easier approaches is to simply hike up to Prominent Point then traverse around the backside of Dome Rock on the connecting ridge.
The much better approach is to hike Quiet Canyon, enjoying that very pleasant rock bound enclosure until you emerge from the short, dark rock narrows .2 mile below the big waterfall. At this point instead of continuing on up to the falls, exit the canyon in the drainage on your right and follow the obvious and very steep course right up the left side of Dome Rock. You may be tempted to angle to your right, softening the climb across the meadowy western ridge, but if you decide to take that route, you might as well carry it all the way around to the far west face, completely circling the Dome, coming up on the south side of the formation. That is not a difficult route, but it is prickly. Wear gloves and watch where you place your hands... and feet... and legs.
Whichever route you use to get to the top, it will not take all that long. Enjoy the views of the highly contorted contours of rock layers. In fact, the lower views are the better ones in this case. Once on top, it feels like you are simply back on one of those prickly ridges. The views are all city sites. That is the nice aspect of approaching the Dome from Quiet Canyon. At least for awhile you'll feel as if you are off and away.
It's hard to spend much time in Alamo and not wonder about what it would be like up on top of that rock. The crazier of the hikers may wonder about climbing up and over that rock, and there are a number of obvious routes around on the west side that look inviting... not to me, but I'm not one of those crazies! This is a great short hour outing. Make the effort and you'll never again mistake this one for Prominent Point.
WARNING! Hiking and outdoor related sports can be dangerous. Be responsible and prepare for the trip. Study the area you are entering and plan accordingly. Dress for the current and unexpected weather changes. Take plenty of water. Never go alone. Make an itinerary with your plan(s), route(s), destination(s) and expected return time. Give your itinerary to trusted family and/or friends.