Located just north of City of Rocks National Preserve in Cassia County, Idaho, Castle Rocks State Park is well worth a visit. You can't camp there, but you may picnic, hike, and climb rocks to your heart's content. Names like "Big Time" and "Poultry Pillar" point from the trail to the climbs--and the climbers. People leave by noon to conquer other ascents, leaving the vistas to us flatlanders.