We planned a training day trip, with 20-30 lbs backpacks, up the switch backs towards Condor Gulch and then back into the caves of Bear Gulch.
Originally the trip was planned for 5-6 miles, though we added a trip from the visitor center to Bear Gulch, as the parking lot there was full. There is a shuttle between both locations, though the wait can be long on popular hiking days.
Since there are several caves, do bring a headlamp. And plenty of water.