The Museum für Moderne Kunst is a Frankfurt museum dedicated to contemporary art. Inaugurated in 1991, the museum is housed in a building designed by the Viennese architect Hans Hollein. Given its particular triangular shape, the museum is also popularly known as the slice of cake. Its collection consists of over 5000 works created from the 60s of the twentieth century until today, becoming one of the most important contemporary art collections in Europe. The central nucleus of the collection is formed by the works of Pop Art and Minimalism donated by the collector Karl Ströher. Within the collection there are works of photography, painting, sculpture, drawing, video installations and performance art. Works by artists such as Jasper Johns, Robert Rauschenberg, Carl Andre, Alighiero Boetti, John Chamberlain, Dan Flavin, Donald Judd, Roy Lichtenstein, Walter de Maria, Robert Morris, Claes Oldenburg, James Rosenquist, Frank Stella, Cy Twombly, Andy Warhol stand out , Tom Wesselman, George Segal. On the occasion of the 20th anniversary, in 2001 the entire inventory was digitized as an online catalog on the museum's website and made available to the public. The online catalog is progressively expanding to include informative materials such as texts, short videos and audio documents on artists and works. Since 2007, the Museum für Moderne Kunst has expanded its spaces with two other exhibition venues: the Zollamt (former customs office) and the Tower, where numerous temporary exhibitions are held.