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 archaeological resources. To be included on the National Register, properties must normally be fifty years old, must meet specific federal criteria, and must be nominated following local, state, and national guidelines.
A National Register listing does not by itself bring any preservation requirements, restrictions, or protections. Listing, does, however, make some properties eligible for U.S. and Iowa historic preservation tax credits that can provide reimbursement for up to 45% of qualified rehabilitation expenses. Guidelines are available from the State Historic Preservation Office of Iowa.
The National Park Service Database of National Register properties is available here. In most cases, Decorah's registered sites can be found on the drop-down menu above. Note that there are additional National Register sites near Decorah that are not under the jurisdiction of the Decorah Historic Preservation Commission.