Indian Mound Reserve

Williamson Mound State Memorial Pollock Works
U.S. National Register of Historic Places
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Location	Indian Mound Reserve, 2750 U.S. Route 42
Nearest city	Cedarville, Ohio
Coordinates	39°44′23″N 83°49′24″W / 39.73972°N 83.82333°W / 39.73972; -83.82333Coordinates: 39°44′23″N 83°49′24″W / 39.73972°N 83.82333°W / 39.73972; -83.82333
Area	1.7 acres (0.69 ha) (W) 8 acres (3.2 ha) (P)
NRHP Reference #	71000639 (W) 72001014 (P)
Added to NRHP	December 13, 1971 (W) February 23, 1972 (P)

Indian Mound Reserve is a public country park near the village of Cedarville, Ohio, United States. Named for two different earthworks within its bounds — the Williamson Mound and the Pollock Works — the park straddles Massie's Creek as it flows through a small canyon.

Both forks of Massie's Creek flow through Cedarville Township from the east to their confluence in the township's center, whence the creek flows westward toward the Little Miami River. For the first 2 miles (3.2 km) below the confluence of the forks, the creek utilizes a shallow but sheer canyon that reaches as deep as 40 feet (12 m) below the surface of the surrounding terrain. Nathaniel Massie is reputed to have battled a Shawnee band under Tecumseh and forced them over the stream at the canyon. By the early twentieth century, local residents had known the vicinity of the "Cliffs" as a picnicking ground for the past hundred years, and calls were being made for its conversion into a park. In 1929, owners D.S. Williamson and a Xenia bank donated the Williamson Mound to the Ohio Historical Society. Today, Indian Mound Reserve is operated as a unit of the Greene County Parks, which uses it to host events such as children's camps. Hiking trails, picnic grounds, a log cabin, Cedar Cliff Falls, and the ancient earthworks are among the attractions within the park, which lies along U.S. Route 42. The earthworks are located on opposite sides of the creek: the Pollock Works on the southern side, and the Williamson Mound approximately 100 rods (1650 feet, or 500 meters) away on the northern side.