WHEN YOU’RE LOOKING for the Robert Rauschenberg archive, everything starts to resemble a Rauschenberg. The chance juxtaposition of a vibrant yellow school bus next to a red Staples sign seems somehow intended, part of the artist’s grand design. So too might the pale lavender blossoms of wisteria that frame the gray painted door tucked away in a hardscrabble industrial zone of lots and chain-link fencing.

Behind that door in Westchester County, N.Y., is an astounding secret: a fluorescent-lit hangar hung with nearly a hundred rusty bicycles; Rubbermaid tubs full of old neckties and scraps of bright, patterned fabric; boxes marked “Polaroids” and “Playing cards from Japan”; dark blue bags labeled “Merce Mannequins” (Merce Cunningham, the dancer and choreographer, was the artist’s friend and collaborator) and file cabinets, some still taped shut, containing folders of ephemera along with correspondence from the likes of Jacqueline Onassis, Jasper Johns and Richard Gere. Rauschenberg purchased the high-security warehouse, which contains areas for art conservation and cold storage facilities, in 2006, to consolidate his art holdings. After the artist’s death at age 82 in 2008, it took four years for his assets to be transferred from the estate to the Rauschenberg Foundation; after that, most of the contents from his properties in Manhattan and on Captiva Island, Fla., were packed up and transported here. Earlier this year, a team of archivists started to unpack the shipment, which includes 269 boxes of paper, 50 boxes of audiovisual data and 45 boxes of “source materials”: the things Rauschenberg kept around him that he might one day have turned into artworks.

A source material, for Rauschenberg, could have been almost anything. Among the most prolific and consistently surprising American artists, he worked for over 50 years in a variety of media from feathers, stuffed goats, socks and neckties to cardboard, grass and scrap metal, in genres including choreography, costume design, photography, printmaking and painting. He is most famous for the “combine,” a form he more or less invented that merged three-dimensional collages with sculpture, sometimes with the batty ingenuity of a Rube Goldberg. Few works capture so arrestingly the process that brought them into being: In a finished Rauschenberg, you see a goat, a tire, a tennis ball, but more than that, you see the insights that brought them together. Each component keeps its integrity within a composition in which everything contributes to a profound effect of overall beauty. Indeed, few artists of his era so unabashedly strove for beauty, even majesty: The logic of his work, beginning with cast-offs and flotsam, demanded it. It was the dare he put to himself in everything he made.