The Trail of Two Forests offers a unique hiking experience through two forests that stand side by side but are separated in age by 2,000 years. One forest consists of old-growth Douglas-fir and western red-cedar, while the other is a young forest that was engulfed by lava flows from a Mount St. Helens eruption over two millennia ago.

Formerly known as the Lava Cast Forest, the younger forest features three-dimensional imprints of trees in the old lava beds, known as lava casts. The boardwalk trail loops through these two forests and is both kid- and wheelchair-friendly.

Around 1,900 years ago, fluid lava flowed through a stand of trees, burning them but leaving impressions where they stood or lay. This type of lava was much more fluid than the sticky lava that forms the dome in the crater of Mount St. Helens today.

When visiting the Trail of Two Forests, please stay on the trail to protect the fragile mosses and surrounding features of the forest.

One highlight along the boardwalk is a ladder descending eight feet into a lava-cast tree mold. Hikers can crawl through the tree mold, an activity especially popular with youngsters. Bringing flashlights and wearing old, warm clothes is recommended for this adventure.

Driving Directions

1. Drive east from I-5 on Highway 503 as it changes to Forest Road.
2. Pass the town of Cougar, and 1 mile beyond the Swift Dam (about 35 miles from your turn off I-5), make a left onto FR 83.
3. Proceed two miles and turn left onto FR 8303.
4. The trailhead is on the left, a half mile away.