"Mother Nature sometimes provides unique treats for kids, and this is one of the best examples: a deep basalt gorge to explore, with a dark 200-foot-long cave/tunnel, so cold that on a hot day it feels like you’re stepping into a refrigerator.
The day we were there children from two families, ages three to twelve, were having fun listening to their echoes, exploring the tunnel, and throwing rocks into the pool. The last we saw of them they were happily investigating other caves. Boulder Cave is the official name, but since you can walk through it, you could easily call it a tunnel. Be sure your family has a flashlight or, better yet, two or three, because the inside of the cave/ tunnel is dark."