I have been to Zion a few times and it really is a site to be seen time and time again. The best part is to start is wind your way up to the tunnel. You can see several of the cut outs from the road below if you are looking for them. Once inside the tunnel, run your engine up and hire the echo's. We were with a group of Harley riders and the noise was music to our ears. It is a long tunnel but you cannot stop to see out the cutouts.
Fabulous place to drive through, walk around or hike into the further trails just off the road.