The fossils at Painted Hills, a unit of the John Day Fossil Beds National Monument, date back about 33 million years, and reveal a climate that has become noticeably drier than that of Sheep Rock's era. The eroded buff-color hills reveal striking red and green striations created by minerals in the clay. Come at dusk or just after it rains, when the colors are most vivid. If traveling in spring, the desert wildflowers are most intense between late April and early May. Take the steep, ¾-mile Carroll Rim Trail for a commanding view of the hills or sneak a peek from the parking lot at the trailhead, about 2 miles beyond the picnic area. A few Forest Service roads lead north toward the Spring Basin Wilderness and the town of Antelope, but these can only be managed safely by high-clearance vehicles and when dry.