The National Register Information System (NRIS) is a database of properties that have been listed on the United States National Register of Historic Places.
[1] The database includes approximately 45 pieces of data for each listed property.
For example, a 2004 paper addressed accuracy of spatial location data for part of the NRIS content.
[5] A search interface within the National Park Service's NPS Focus system provides access to a skeletal record of NRIS data, as well as to photographs and documents describing properties listed on the National Register.
The skeletal record includes a simplified set of the information in NRIS about all sites listed through August 2012.