Too hard for children ?
No big hills. maybe let the kids set the pace and they will be fine. If you see a ranger they will open the ranch house anytime and check out the inside of the artisan well house
6.8 mile loop trail but there's plenty of interest close to the trailhead inside the park. There is the old ranch house, a creek with crayfish, wooden foot bridges and the trees keep a lot of it shaded.
Not sure about mileage. But the trails are easy to walk on. Getting to the waterfall and back might be long for kids depending on their age. It's beautiful though and you can always turn around when you're tired =]
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