The book No Limit offers a new look at the ring road round Paris and looks at possible transformations by working on, beneath and against the infrastructure, all at once. By closely examining this long abandoned area and inventing a specific mapping, the book first describes the differing relations between the ring road and the city by way of “16 metropolitan identities”, then takes a closer look at six of them which are involved in possible transformation projects around this infrastructure. But without erasing its main value, needless to say, which, like the river Seine and in a contemporary version, turns it into a large metropolitan open space.