The Ape Caves are on the south side of the mountain. Try staying in Woodland there are a couple nice parks, Woodland Shores right in Woodland the other is on the dike road right onthe Columbia river. That KOA you asked about is all up n down hill hard to even walk around too steep. You would enjoy your trip more going to Woodland also you can get closer to the crater at Windy Ridge plus there is Lava Canyon and alot of great fishing and swimming lakes. TheKOA has a pool table thats it!
Nice place to stop off on your way north. Going to visit Mt. St. Helen's from here includes several well designed visitor centers that tell the whole story about the eruption. The Ape Caves are a drive from either woodland or castle rock.
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