The collection consists primarily of works, correspondence, diaries, documents, photographs, maps, scrapbooks, miscellaneous material, and printed matter by and about Thorington (Princeton Class of 1915), and papers of other people. The works include manuscripts for three books, A Climber's Guide to the Rocky Mountains of Canada (1921), written in collaboration with Howard Palmer, The Glittering Mountains of Canada (1925), and Mont Blanc Sideshow (1934), a biography of Albert Smith (1816-1860), a renowned mountain-climbing guide of the 19th century. There are also over thirty-six articles (1916-1934) reflecting Thorington's interest in mountaineering, many of which were published in the American Alpine Journal. The correspondence contains many letters to and from the American Alpine Club, alpine clubs of Canada and England, and individual mountain-climbing enthusiasts and friends of Thorington. There is also correspondence regarding the early American ascents of the Alps which contributed to the body of information in his book A Survey of Early American Ascents in the Alps in the Nineteenth Century (1943).

The collection contains many photographs of friends and Alpine and Rocky Mountain ranges, as well as the towns of Chamonix, France, Cortina d'Ampezzo, Italy, and Zermatt, Switzerland, and there are travel slides and films, diaries, a scrapbook of pictures and pencil sketches of Alpine animals, and printed matter, including articles and book reviews by Thorington.

Papers of others include the typescript of Conrad Kain's Where the Clouds Can Go (1935), edited, with additional chapters, by Thorington; Kain's correspondence with Amelia Malek and articles by Kain; letters by Majorie and Francis P. Farquhar to friends describing their round-the-world airplane flight (1951); diaries (1926-1935) by Andrew Morrison Taylor; photographs and films by Edgar F. Farmer; articles by Allen Carpe and Noel Ewart Odell; letters by William Sargent Ladd and D. R. Smith; and the Thompson-Little Collection of material including a genealogy of the Thompson family and letters and photographs dealing with mountaineering in the Canadian Rockies and Selkirks.