In the early 1990s, Martin Kippenberger (1953–97) developed the idea of a global underground network: METRO-Net. Although it is one of the artist’s most fascinating projects, his premature death in 1997 meant that it could only be implemented in rudimentary form. In 1993, a metro entrance was built on the Greek island of Syros, followed by two more: one in 1995, in Dawson City in Canada, and the other in 1997, on the new Leipzig exhibition grounds. These structures proposed a means of traveling in the boundless space of the imagination: without the willingness to visualize tunnel tubes and moving underground trains, this project remains a “nonsensical building plan.” But the moment we accept the artwork as a mode of transport for “mind travelers,” then the full power of this work unfolds. Documented in this volume, Kippenberger’s METRO-Net was intended to counter life’s predictable, rationally oriented parameters with a romantic sense of the world.