Sunnyside, Historic plantation on Edisto Island, South Carolina.

Sunnyside, also known as the Townsend Mikell House, is a plantation house at Edisto Island, Charleston County, South Carolina. The main house, built about 1875, is a 1+1⁄2-story rectangular frame residence clad in weatherboard, with a mansard roof topped by a cupola and a one-story hipped-roof wraparound porch. The property also holds the tabby foundation of a cotton gin, two small one-story gable-roof outbuildings, a 1+1⁄2-story barn and the Sunnyside Plantation Foreman's House, a two-story frame dwelling built about 1867.

The estate was an important center for agricultural development on Edisto Island and played a role in the economic history of the Lowcountry region. Its structures document different periods and methods of farming over several centuries.

The property includes buildings that reflect how people lived and organized daily activities on this South Carolina estate. These structures show the social patterns that shaped life in this agricultural setting.

The grounds are privately owned and visitors should obtain permission before accessing the property. It is recommended to clarify access options in advance, especially if you plan to conduct any research activities.

The property preserves the tabby foundation of a cotton gin, a concrete reminder of the plantation's cotton processing. The Foreman's House, a two-story weatherboard frame residence built about 1867, predates the main house by roughly eight years. Both were included in the 1986 National Register listing, with a boundary increase in 1994.