This upland forest spreads across several recent lava flows. A rugged trail follows a 2-mile loop past a pit crater, winding around interesting trees such as hau and kukui. It's a nice spot to get out of the car and stretch your legs—you can wander through the well-maintained arboretum, snap a few photos of the eerie forest, and let the kids scramble around trees so large they can't get their arms around them. The pathways can get muddy and rough, so bring appropriate shoes if you plan to hike. Restrooms, picnic areas, and camping sites (by permit) are available.
Hwy. 11, north of mile marker 81, Hawaii, United States