From the park entrance, drive about 1/2 mile to a visible trailhead on left. There are no signs but it is near a brown post with a wind gauge and antenna. Trail goes through an amazing cedar forest then crosses a stream.
The cache is at the base of a bush-like tree. From the cache location you can hear a hidden waterfall (most of the year.) After you've found the cache, follow the sound to see a pristine mini-waterfall!
Be sure to watch the time if you arrive late, they lock the entrance at 6PM.