In 1993, Martin Kippenberger inaugurated the first work in his METRO-Net World Connection project, an expansive and idealistic vision of a linked subway system that spanned the globe. As an extraordinarily rare example from this body of work, Gagosian’s presentation of METRO-Net Transportabler U-Bahn Eingang (METRO-Net Transportable Subway Entrance) (1997) at Art Basel Unlimited in 2025 marks a unique opportunity to join this important postwar artist’s network, both real and imagined. One of only two non-site-specific subway entrances he ever created (the other is in the permanent collection of the Museum of Modern Art in New York), Kippenberger’s Transportabler U-Bahn Eingang conveys a grand and poetic longing for interconnection. Yet it also maintains the artist’s characteristic cynicism regarding the feasibility of such utopian aspirations. Conceived shortly before Kippenberger’s untimely death in March 1997, this sculpture is one of the last ever pieces that he worked on in his lifetime.

In 1992, while on an extended retreat at the family home of his friend Michel Würthle on the Greek island of Syros, Kippenberger envisaged one of the most important, emblematic, and wide-ranging projects of his career. Rather than luxuriating in his coastal surroundings, the artist was inspired by the distant locale to develop the METRO-Net World Connection project. This elaborate endeavor comprised multiple full-scale simulated subterranean subway entrances and later, ventilation shafts, which the artist installed in sites ranging from the far-flung Arctic town of Dawson City, Canada, to the German city of Leipzig. Despite the optimistic tenor behind the concept of creating a global community through art, METRO-Net notably emerged from Kippenberger’s idea of “unsinnige Bauvorhaben” (“senseless building projects”) and contains one extremely unusual feature. All five of the subway entrances that Kippenberger built led to impenetrable locked gates or doors. This impasse powerfully represents the theoretical nature of Kippenberger’s concept, a passage that culminates in a dead end.

Initially Kippenberger developed several permanent, site-specific entrances, customized using the architectural vernacular and local materials from the place in which each is situated. In September 1993, the first entrance opened on Würthle’s property in Syros. It comprised a concrete stairway leading underground to a cast iron gate marked with the emblem for the Lord Jim Lodge, a secret society cofounded in the mid-1980s by Kippenberger with fellow artists Wolfgang Bauer, Albert Oehlen, and Jörg Schlick.

Two years later, Kippenberger created a wood version of the METRO-Net subway entrance near a friend’s hotel in Dawson City, which featured not only the Lord Jim Lodge motif, but also the letters “NHN,” shorthand for the Lodge’s motto, “Nobody Helps Nobody.” In late 1995, Kippenberger began work on a third in-situ subway entrance for the Leipzig Trade Fairgrounds, which opened in 1997. Notably, none of the locations in which he built subway entrances have actual underground subways in operation, further emphasizing the strictly symbolic and artistic nature of his project.

In 1997, on the occasion of his forthcoming inclusion in Documenta X, the prestigious contemporary art exhibition in Kassel, Germany, Kippenberger developed a new, transportable version of the project that allowed for infinite installation possibilities. Meticulously planned, this iteration (the present work), unlike its predecessors, was entirely detached from the ground—granting access to Kippenberger’s imaginary underground network from any point in the world.

The Transportabler U-Bahn Eingang therefore marks an important evolution of Kippenberger’s initial concept. This imaginative and visually stunning work contains all the key components: a descending staircase, safety railings, and other conventions of public transport. At the bottom of the stairs is a padlocked chain and a plaque that reads “Eintritt verboten” (“Entry prohibited”). Beyond stands a grand ornamental locked gate adorned with the emblem of the Lord Jim Lodge, incorporating three symbols: the sun, breasts, and a hammer.

As seen in renderings, the artist initially imagined installing the sculpture on the water, partially submerged in Kassel’s Fulda River like a barge. With the help of engineers, Kippenberger successfully designed the construction to float; ultimately, however, by November 1996 the artist and Documenta staff agreed to instead place the work on a nearby river embankment. Exhibited in this manner, with no subterranean aspects, the sides and other previously unseen elements of the sculpture become fully visible, allowing the artist’s complete design and concept to be grasped.

Constructed in lacquered steel, Kippenberger’s Transportabler U-Bahn Eingang on view at Art Basel Unlimited closely resembles the first permanent sculpture from this project in Syros, with the added feature of being able to be installed indoors or outdoors, based on the owner’s preferences. The second, aluminum version of Transportabler U-Bahn Eingang from the METRO-Net project was first shown at New York’s Metro Pictures in 1997. However, due to size constraints, the work had to be crushed to fit into the gallery, and therefore, while approved, this METRO-Net Transportable Subway Entrance (Crushed) (1997) is not original to the artist’s initial plans.

In addition to the subway entrances, Kippenberger also conceived of an adjacent aspect of the METRO-Net project: a set of oversize ventilation shafts, which would simulate the gusts of air and sounds made from trains passing underground. Initially planned for Tokyo, one of these was realized in 1998 at the famed Schindler House in Los Angeles, owned by the MAK Center for Art and Architecture. A fully above-ground iteration of the ventilation shaft was presented at the renowned Skulptur Projekte Münster in Germany in 1997.