This is a perfect hike if you want to get a feel for Washington's forests, though it's not necessarily indicative of what the rest of the Mount St. Helens National Volcanic Monument is like. The north side of St. Helens was the least affected by the 1980 blast, and the forest that the Goat Creek Trail winds through is home to huge, old trees that survived the eruption that obliterated the forests on the other side of the mountain.
The trail leaves a small parking area large enough for five cars and traverses the hillside through quiet forest of red cedar and hemlock. Mossy rocks, and plenty of trailside distractions like chipmunks and slugs will keep kids entertained. Continue gently climbing to Cathedral Falls, the highlight of the hike. The trail provides an intimate, 360-degree view of the falls, leading hikers towards the base of an enormous waterfall, and then winding behind it.
Hike under a cave and enjoy the spray from the falls, but be careful — the trail drops steeply away off to your left here and a wrong step can mean a far fall.