Established in 1926, the History Center of Olmsted County (HCOC) collects, preserves and interprets the history of Olmsted County. The HCOC actively serves Olmsted County and the SE Minnesota region by offering a varied presentation of educational and outreach programs, special events, museum exhibits, a research center and archives. The HCOC owns and operates a number of historic structures. The Historic Mayowood Mansion, and the George Stoppel Farmstead, both are listed on the National Register of Historic Places. The 1860's William Dee Cabin, 1880's Hadley Valley Country School, and Ralph Stoppel Farmstead complete the list. The organization's operations are managed by a professional staff in conjunction with more than 400 enthusiastic volunteers.