Near Ape Caves was also the Trail of two Forests.
On one side is what’s left from the devastation of Mount Saint Helens’ explosion (2000 years ago, not the one my parents remember) and the other side was relatively untouched.
The coolest part to me was the holes made from the trees. (This is from memory so hopefully it’s factual… ;). The large trees were burning from the inside while the lava was on the outside so it left these tree molds.
They put a ladder into one of them where you can go down and then through a mini lava tube and out further down.

I went through but my 6’ husband couldn’t shimmy through so he went on the board walk with our toddler.
It’s really amazing how lava from so long ago can really change the scenery.