Ape Cave is about 9 miles east of Cougar, WA, which is the nearest town to Castle Rock in the usual route people mean. The cave itself is roughly 2.4 to 2.5 miles long, but if you meant the driving distance from Castle Rock, it’s about a 40- to 50-mile drive depending on your starting point in Castle Rock and the exact route you take.

Route context

From Castle Rock, the trip generally heads east toward the Mt. St. Helens area and then onto Forest Road 8303 near Cougar. The official Ape Cave access page places it approximately 9 miles east of Cougar, which helps pin down the last leg of the drive.

Quick note

People sometimes ask “how far” when they mean either:

  • driving distance from Castle Rock, or
  • the cave’s own length.

Ape Cave’s length is about 13,042 feet, or around 2.4 miles.