Pickle Springs is a 256.5-acre protected natural area in Missouri, near Hawn State Park and Farmington, recognized as a National Natural Landmark. Its steep rocky slopes and small box canyons, locally called shut-ins, block direct sunlight and create cool, moist pockets within the landscape. Seasonal waterfalls along the canyon walls help sustain relict species that are rare in southern Missouri, including ferns and amphibians more commonly associated with the North American North Woods. A 2-mile hiking trail provides access to this compact but distinctive reserve, valued for preserving an unusual mix of rugged geology and sheltered habitats.