This shuttle hike packs a whole lotta geologic marvels into a few beautiful miles: petrified trees, basalt columns, and plunging canyon cliffs, to name a few. Start by dropping a car or bike at the Yellowstone River Picnic Area, then proceed to the trailhead for the unnamed but official trail (not to be confused with the Specimen Ridge Trail). From here, you’ll climb steeply to excellent views over the Lamar Valley and Absarokas until you reach a rocky outcrop scattered with fossilized, 50-million-year-old sequoias, firs, and other trees. Take care in this area, as it’s quite steep, and resist the temptation to take a fossil home—not only does that damage the precious resource, it’s also illegal. Continue west across a sage-filled meadow on the Specimen Ridge Trail (it’s faint up here) to the east rim of a narrow canyon on the Yellowstone River; trace the rim northwest on the Yellowstone River Picnic Trail, looking out for osprey, peregrine falcons, bighorn sheep, and the distinctive volcanic basalt columns across the river. The trail will take you back down to the picnic area.