Driving to Bryce and Zion from St George doesn't involve driving along cliffs.
Thanks, RedRox. That's a relief.
The short drive between Zion and Zion Mt Carmel tunnel has switchbacks and drops off but millions have survived.
We have someone that travels with us with that same issue, and have been to Zion and Bryce many times, and they were never uncomfortable.
So, I would just rent a car as suggested.
Is there some reason why you would be staying in St George? Although there is plenty to do there and its a nice small town, If you want to visit ZIon, you may want to stay in Springdale which is right near the entrance to Zion.
However, if you decide you want to stay in St George, here is a good thread with things to do in the area.
Here is a website that includes information on Tours of Bryce Canyon:
I'll drive you through the treacherous Zion switchbacks. Its my favorite drive. Just shoot me a message when you get here. Its a must do...put your game face on and conquer your fear.
Not sure the OP is still reading this thread. He/she never came back.
We actually were there Dec. 1 - 7. Drove and managed to survive it with a few apprehensive moments. All worth it as Zion was stupendous. Went to Bryce as well but liked Zion better. Thanks for all your concerns and advice.
Glad to hear that it worked out for you. The scenic hwy through Zion is nice because you can almost drive at your own pace.
Thanks for the feedback. Glad you''ve had a nice trip.