Mount Adams Wilderness is a federally protected area on the western side of Mount Adams in Gifford Pinchot National Forest, preserving 47,708 acres of volcanic, geologically active terrain around Washington’s second tallest mountain. Its landscapes shift sharply with climate, from drier and wetter forests to alpine parklands, lava flows, rimrock, streams, glaciers, and wildflower meadows. Potato Hill, a late Pleistocene cinder cone on the north side, also serves as a weather observation site with deep seasonal snow. The wilderness is a major destination for hiking, horseback riding, backpacking, and climbing, with extensive trails around the mountain and challenging high-elevation routes that require caution.