This PhD thesis concerns urban mining, an umbrella term for different recycling strategies aimed to recover materials from the built environment. More specifically, it focuses on hibernating urban infrastructures, that is: cables and pipes that have been left behind in their subsurface location after they were disconnected. I term this subsurface urban realm of system rejects the "Urk World". "Urk" is short for "urkopplad", the Swedish word for "disconnected", an abbreviation often found on old infrastructure maps denoting discarded system parts. Since urks contain high concentrations of copper, my normative stance is that the Urk World should be "mined" as a contribution towards diminishing the persistently wasteful handling of mineral resources in society. Keywords: urban mining, hibernating stocks, infrastructure studies, urban metabolism, material flow analysis 1.1 Why Study the Urk World? 2. The Objectives of the Thesis 5 2.1 Knowledge Cluster 1: The Dawn of the Urk World 2.2. Knowledge Cluster 2: Mining the Urk World 2.3. Knowledge Cluster 3: Do Urks Have Politics? 2.4 The Structure of the Thesis 3. The Rationale of Studying the Urk World 9 3.1. Why the Focus on Cupriferous Urks? 3.2 The Environmental Argument for Copper Recycling 3.3 The Ethical/Degrowth Argument for Copper Recycling 3.4 The Social Argument for Copper Recycling 4. The Scientific Underpinnings of the Thesis: The Interdisciplinary Study of Infrastructures 15 4.1 Introducing Urban Metabolism and Infrastructure Studies 4.2 The Urk Worlds Assessed in the Thesis 4.3 The Appended Articles and Methods Used