Pikes Peak is itself, an intrusive center and smoky quartz and amazonite can be found in many areas within four miles (6 km) of the summit. For example, amazonite can be found next to Barr Trail, the main hiking route to the summit of Pikes Peak. The most famous collecting area on the Peak is Glenn Cove, a glacial cirque located at on the north side of the mountain. Quartz crystals, amazonite and topaz crystals can be found in pockets on steep cliffs in this area.