National Register of Historic Places
The National Register of Historic Places is the official list of the Nation's historic places worthy of preservation. Authorized by the National Historic Preservation Act of 1966, the National Park Service's National Register of Historic Places is part of a national program to coordinate and support public and private efforts to identify, evaluate, and protect America's historic and archeological resources.
Historically significant properties which are at least fifty years old and are associated with historic events or people, represent distinctive architecture or construction, or provide important information on prehistory or history may qualify for either or both the State and National Registers of Historic Places. The eligibility of properties for the State and National Registers of Historic Places is governed by broad guidelines and rules.
NPS NRIS Database (National Park Service National Register Information System)
NPS Focus Digital Library & Research Station is a growing collection of thousands of images, documents, drawings and maps about the cultural and natural resources maintained by the National Park Service. Unlike other digital library projects in the United States, the NPS Digital Library is completely decentralized with separate centers being set up in virtually every State and U.S territory. Each park or program decides what digital resources will be added to its collection on the NPS Focus Digital Library.
National Historic Landmarks Program - National Historic Landmarks program differs from the National Register of Historic Places program. Landmarks have been recognized by the Secretary of the Interior as possessing national significance. Nationally significant properties help us understand the history of the Nation and illustrate the nationwide impact of events or persons associated with the property, its architectural type or style, or information potential. A nationally significant property is of exceptional value in representing or illustrating an important theme in the history of the Nation. Properties listed on the National Register are primarily of State and local significance. With a State or locally significant property, its impact is restricted to a smaller geographic area.
SD State Register - List of properties on the State Register of Historic Places