The Honey Hollow Watershed is a 650-acre (2.6 km2) watershed on the south side of the Delaware River a few miles north of New Hope, Pennsylvania. It is the site of the first privately owned soil conservation district in the United States. Created by five landowners in 1933, it was successful in mitigating the effects of erosion caused by the introduction of modern agricultural methods in the early 20th century. The area was designated a National Historic Landmark District in 1969.