Musée d’art moderne, Département des aigles, Section XIX siècle. (Museum of Modern Art, Eagle Department)
This is actually a fictional institution, a monumental work of conceptual art in itself - at the time it opened (1968), Brussels had no Museum of Modern Art. (And this endeavor was a jab at the lack as well.)
His “museum” was open from 1968–1972, in various locations; 1969 in Antwerp, 1970–1972 Düsseldorf and the second half of 1972 in Kassel, with new sections at each opening - “Section XVII”, “The Cinematic Section”, “The Section of Figures”. The Department of Eagles opened in 1968, and was filled with…all sorts of stuff, featuring eagles - sculptures, stuffed specimens, lighters, buttons, picture books…and before every display case was stuck the label “Ceci n’est pas une oeuvre d’art” - This is not a work of art.
In 1972 Marcel Broodthaers exhibited Musée d'Art Moderne, Département des Aigles, Section des Figures (Der Adler vom Oligozan bis Heute). This installation housed over 300 representations of eagles from art history and popular culture classified in a pseudo-museological manner—undermining both the mythology of the eagle and the power of the museum. The artifacts were accompanied by numbered labels declaring, "This is not a work of art," in English, French, and German.