This collection primarily consists of maps, plans, and drawings of Centennial grounds and Centennial buildings. The collection is especially strong in items relating to the Art Gallery (Memorial Hall), Horticultural Hall, the Main Exhibition Building, and Machinery Hall. There are a very limited number of related correspondences and advertisements housed within this collection, as well as plans of machinery to be used in buildings during the Centennial Exhibition (such as air conditioning and heating systems). The vast majority of items were created between 1874 and 1877; however a very limited number of later restoration plans of buildings are included. Medium and material vary widely throughout the collection, and include paper, linen, blueprints, bluelines, and lithographs. There are a number of original documents created and/or approved by major Centennial architects H.J. Schwarzmann, Henry Pettit, Joseph M. Wilson, and Alex B. Bary. Only items which were definitely linked to these architects were tagged as such.