There’s no more impressive trail building in the national parks than the work of the Depression-era Civilian Conservation Corps, a publicly funded work program. Along this 8.5-mile counterclockwise loop, where California condors perch atop spires like gargoyles, CCC workers carved rock steps like those cut by Ancestral Puebloans, but installed steel railings for the faint of heart. At the Balconies Caves, the trail threads under enormous volcanic boulders—don’t forget your headlamp. Contact (831) 389-4427; nps.gov/pinn
Get the story behind the High Peaks–Balconies Caves Loop, Pinnacles National Park, California—and how to see it yourself.