The collection contains correspondence, diaries, articles and addresses written by Darling, a subject file, personal financial materials, news clippings, photographs, and engineering plans.

The collection consists of the Commission's files incuding: application to the American Revolution Bicentennial Commission to become a bicentennial city, articles of incorporation and by-laws, financial records, correspondence, manuscripts on local history that were published in the book Duluth: Sketches of the Past, project files by month, Voyageurs Canoe Trip reenactment files, news clippings, brochures and programs, photographs, and proposals.

The collection contains minutes, financial books, annual reports, publications, maps, miscellaneous correspondence, news clippings, photographs, timetables, and microfilmed scrapbooks. Financial records represent the largest portion of records, and there is a significant lack of executive records.

The collection consists of certificates of incorporation and by-laws and a history of the company; minutes 1908-1910; titles, leases, deeds 1887-1959; contracts, correspondence and minutes; stock ledgers 1902-1913; financial statements and balance sheets 1919-1944, 1945-1957; personnel 1956; appraisal 1917; and one black and white photograph of the buildings.

The collection contains personal and financial correspondence, letterpress books, scrapbooks, newspaper clippings, manuscripts written about local and family history, financial records, legal papers, maps, photographs, one audio cassette of an interview, and reference materials.