Jethro Coffin House
Jethro Coffin House, also known as the Oldest House, is a saltbox house built in 1686 and located on Sunset Hill Road in Nantucket, Massachusetts, is the oldest house on Nantucket in its original location and is the only surviving structure from the island's 17th Century English settlement. It is a U.S. National Historic Landmark. Because of the brick design on its chimney, it is also called the Horseshoe House.

The house was built in 1686 as a wedding gift for Jethro Coffin, a blacksmith, and his bride, Mary Gardner (granddaughter of Thomas Gardner (planter)). Jethro Coffin was a grandson of Tristram Coffin, one of the island's original proprietors. It was abandoned by a later owner during the Civil War. The Nantucket Historical Association (NHA) acquired the property in 1923. The house was struck by lightning in 1987 and nearly cut in half, but was carefully restored by the NHA. It was declared a National Historic Landmark and listed on the National Register of Historic Places in 1968. It is located on Sunset Hill Road, in Sunset Hill, Nantucket.