Sylvanus Selleck Gristmill

The Sylvanus Selleck Gristmill, also known as the Edwin Knapp Gristmill, is a gristmill at 124 Old Mill Road in Greenwich, Connecticut. It was listed on the National Register of Historic Places in 1990.

It is a small post-and-beam building built by Sylvanus Selleck in about 1796, and is one of only two known 18th-century mill buildings in the state. An addition in about 1850 is believed to be by Edwin Knapp. The mill is a rare surviving example of braced-frame construction, which was once common. The mill was operated until Edwin Knapp's death in 1895.