Troy Meadows is a 3,100-acre (1,300 ha) nature preserve in Parsippany-Troy Hills, Morris County, New Jersey. Along with the Great Swamp, it is one of the remnants of Glacial Lake Passaic. It was designated a National Natural Landmark in 1967. It is the largest freshwater marsh in New Jersey, the Whippany River goes through the swamp before connecting with the Rockaway River. It is part of the Northeastern coastal forests ecoregion.