Martin Kippenberger's Metro-Net project was an ambitious and imaginative endeavor that encapsulated the artist's fascination with global connectivity and transportation. Initiated in the early 1990s, Metro-Net envisaged a worldwide underground network through the installation of conceptual subway entrances, ventilation shafts, and station elements in various unexpected locations around the globe. This project sought to blur the boundaries between reality and fiction, challenging perceptions of space and the utility of art in public spaces.

One of the notable components of the Metro-Net project included a transportable subway entrance titled "Metro-Net Transportable Subway Entrance (Crushed)" from 1997, housed in MoMA's collection. This piece, crafted from aluminum and measuring impressive dimensions, symbolizes the project's global and transitory nature​ (The Museum of Modern Art)​. Kippenberger's project, while never fully realized due to his premature death in 1997, left a lasting impact on contemporary art, signifying a playful yet critical examination of globalization and its effects on local and global identities.

The installations varied from the first entrance constructed on the Greek island of Syros, to other locations such as Dawson City in Canada, and even a portable entrance showcased at Documenta X. Each piece within the Metro-Net series was complete with details that suggested functionality, like ventilation shafts, creating an illusion of a global underground network that was both everywhere and nowhere at the same time​ (Artbook)​.

Kippenberger's Metro-Net stands as a testament to his ingenuity and his ability to conceptualize and connect disparate places and ideas through the lens of art. It plays on the notion of a network that could potentially link the entire world, yet remains rooted in the realm of artistic speculation and intervention, offering a critique of and commentary on the rapid pace of global change and the interconnectedness of modern life.