National Geographic's Found blog takes us for a tour of the extensive photography archive in the basement of their headquarters in Washington, D.C.
Many of the photos have never been published and are rarely seen by the public, so it's a real treat to see all these fantastic stories and images that otherwise would just be sitting in filing cabinets.
Above: An old dog walks on a treadmill as part of an animal health study at Cornell University, November 1956. PHOTOGRAPH BY B. ANTHONY STEWART, NATIONAL GEOGRAPHIC
Three shafts of sunlight illuminate the basilica and its mosaic floor in the Vatican, December 1971. PHOTOGRAPH BY ALBERT MOLDVAY, NATIONAL GEOGRAPHIC
"As the settler encroaches further and further upon the cattle country, the cowboy and the romance of his calling are rapidly approaching the point where they will exist only on the motion picture screen and in the Wild West show," from an April 1916 feature on the United States. PHOTOGRAPH BY FRANKLIN PRICE KNOTT, NATIONAL GEOGRAPHIC
Sons of lumberjacks try to upset one another on rolling log in Hayward, Wisconsin, Feburary 1957. PHOTOGRAPH BY VOLKMAR K. WENZTEL, NATIONAL GEOGRAPHIC