The part that Toni mentioned is just the first stop of 8. I would say 60 to 90 minutes to drive through the park and see all of the stops.
Probably 30 min. It is not a long trail but it is beautiful! Once you cross the bridge go left and keep walking until you see a stop to read about the canyon.
It's a self directed tour. Just have to leave a closing.
I've never actually taken the whole tour, I'll have to take it next time I'm in the area.
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