Mutton Hunk Fen Natural Area Preserve is a 516-acre (2.09 km2) Natural Area Preserve located in Accomack County, Virginia. Fronting on the Atlantic Ocean's to the east, it is also bounded by and to its north. The property contains a rare "sea level fen" community, one of only four in Virginia. Despite the proximity to the ocean's saltwater, freshwater wetland plants are able to survive in this environment due to the influence of freshwater springs. Acidic conditions also encourage the growth of plants normally found in bogs, in addition to tidal freshwater wetland plants; five of the species found at the preserve are regionally rare.