The W.K. Kellogg Arabian Horse Library Postcard and Notecard Collection spans from the 1920s to the 1970s and contains both postcards and notecards with a connection to either the W.K. Kellogg Arabian Horse Ranch in Pomona, California or the Kellogg Company in Battle Creek, Michigan. The postcards mostly depict horses of the Kellogg Ranch but there are also scenic views of the property and Kellogg House, as well as various locations of the Kellogg Company.