I am not a nature lover and I have not seen many rocks throughout my life (we just moved here - maybe there will be more lol)
However, red rock canyon is a great place. There's a little museum you can stop and if you are a hiker (not me) there are a bunch of trails you can stop and there's a map that tells you which trail is what difficulty level.
If you are not looking to do any hiking that is alright as well. There is a 13 mile loop you can drive around slowly and see everything. You can also park and take pics in most places.
Also, it is $7 for a car to get in no matter how many people are inside the car. I thought that was nice too. I will go again one day :)