Overview: Looking for an adventure? Explore a mountain inside and out. Twist and bend through angled marble passages deep underground on a ranger-guided tour of the Oregon Caves. Wonder at the smooth flowstones, stalactites and stalagmites. Above ground, you can hike old growth forests and high mountain meadows, or relax in the Oregon Caves Chateau, a National Historic Landmark. Visit, discover, and have fun. Cave tours run late March through early November. Hiking trails are open year-round.