The Wagner Free Institute of Science is a rare survival—a museum and educational institution that remains nearly unchanged from the nineteenth century in both the arrangement of its specimens and in its mission. Its public courses in science represent the oldest program devoted to free adult education in the United States. In recognition of the importance of this free education mission and of its contributions to science education and research, the Institute was designated a National Historic Landmark by the United States Department of the Interior in December of 1990.