This paper delivers actionable recommendations towards building a rationale for activating and promoting Underground Built Heritage (UBH) based on the nexus heritage, territory and society, and making use of existing literature and findings from five international cases. The research was conducted in the framework of the working group on Planning Approaches of the COST Action Underground4value. The analysis of the cases aims to provide guidelines for this working group and to benchmark good practices in activating UBH. It highlights the importance of community-led initiatives, leadership and dialogue and power sharing between the local/regional authorities and communities aiming for better understanding of the potential of UBH. The successes and/or failures of the five cases emphasise the importance of knowledge and experience in participatory approaches. Success was verified, when effectiveness and democratic principles were combined in the planning process, and local history is integrated with citizen science, co-creation and placemaking. The analysed approaches stimulate a new hybrid layer for activating UBH, provide mechanisms of mediation between people and heritage, and contribute to cultural and social dimensions of sustainability. This is a highly challenging endeavour, as it seeks to support and advance a sound understanding of UBH as a sustainable resource, backed by strategic stakeholder dialogue and contextual knowledge. Such effort requires a dynamic understanding of UBH values, knowledge, abilities and skills, towards creating more effective coalitions of “actors” within localities, by developing structures, which encourage long term collaborative relationships.

This document serves as the opening chapter of a book that addresses the critical issue of resource depletion in the built environment, illustrating the unsustainable trends in current construction and demolition practices that extensively rely on new raw materials. It highlights the significant impact of the building sector on global resource consumption, energy utilization, and waste generation, with alarming statistics such as buildings accounting for 40% of the world’s extracted materials and a significant source of waste and greenhouse gas emissions. Advocating for a transformative shift towards a circular economy in the built environment, the text emphasizes sustainable and regenerative economic practices that minimize waste and maximize resource efficiency. This approach necessitates the redesign of systems to ensure the durability, reparability, and recyclability of construction materials, thereby promoting a model where waste is systematically eliminated and materials are continually repurposed. The document also discusses the 10R strategy, which centres on minimizing waste and enhancing resource efficiency, and explores various circular practices within the construction sector. It includes examples from case studies and best practices to demonstrate the viability and advantages of adopting circular economy principles. The challenges and success factors in implementing such practices are thoroughly examined, emphasizing the urgent need for increased awareness, supportive policies, and robust stakeholder collaboration to foster a more sustainable and resource-efficient built environment. The first chapter sets the stage for a detailed exploration of these themes throughout the book’s subsequent sections.

In recent years, mobile devices have become very popular communication tools that provide access to information and communication, influence people’s social behaviour and change patterns of their everyday activities. The use of communication technologies in public open spaces has become significant for the outdoor experiences of people and the relationship between users and technologically mediated outdoor activities. More specifically, wireless digital cultures not only influence spatial layout, infrastructure systems and moving patterns, but also require ICT-based placemaking strategies. This is often not considered sufficiently during the physical design stage. It is important to consider a space appropriation approach to the use of digital technologies in public spaces, based on user requirements and the local context. This is demonstrated with a case study of the Gardens at new waterfront of Thessaloniki, Greece. In this project space analysis and users’ questionnaires were applied to relate digital space to the reality of the physical landscape as a first stage in the design process. This approach has wider implications for successful place making strategies. This chapter considers the possibilities of extensive outdoor use of digital media technologies in traditional forms of spatial experiences. It proposes that the new digital layer overlaying the physical space should first be methodologically explored in a way that could advance understanding of the extent to which immaterial networks and relationships can affect material planning and design dimensions.

This chapter examines the primary technical barriers and challenges that impede the transition to a circular economy within the built environment. It highlights the complexities involved in integrating circular practices into the industry which traditionally relies on linear models, government and society. The analysis explores technical barriers at the urban, building and material levels of the built environment through a problem-based approach. Findings highlight a lack of standardized methodologies, inadequate design strategies for reuse and adaptability, insufficient data on material performance, and constraints in current construction practices and regulations. Furthermore, it underscores how technical fragmentation and limited interoperability among systems hinder the advancement of circularity. The chapter also explores the potential benefits of digitalization, design for disassembly, and building information modelling (BIM) as a means to address these challenges. Ultimately, it emphasizes the need for coordinated efforts among stakeholders, supported by robust regulatory frameworks and innovation, to effectively implement circular economy principles in the construction industry.

This paper aims to explore public participation for activating underground built heritage (UBH). It describes and analyses practices of stakeholders’ engagement in different UBH assets, based on experiences gathered in the scope of the European COST Action ‘Underground4value’. It brings together five inspiring cases from Italy, Portugal, Spain, Switzerland and the United Kingdom, in which digital and mobile technologies were used as tools to improve community experiences in UBH. Thus, the paper discusses ‘smartness’ from the perspective of people and communities around cultural assets, where ‘smartness’ becomes a new connotation and a pathway to advance (local) knowledge and know-how. Therefore, this paper takes on the challenge to define a smart city as an ecosystem for people’s empowerment and participation, and, in particular, to explore social tools for creating new values in heritage placemaking—where sharing knowledge becomes a fundamental principle.

Interests of young people are neither often well considered in public spaces nor in decisions about the environment around them. One of the most important achievements of growing from childhood to adulthood is the development of one’s own social life and increasing one’s autonomy, which also means a widening of one’s spatial range of action. Despite these spatial needs and benefits for their own development, teenagers are often treated with suspicion in public spaces. One will often find them in large groups, standing around, chatting loudly with one another or playing around. Spatial needs, appropriation and practices, on the one side, and social norms, on the other side, do not necessarily match. In an inclusive city, spatial consumption and production is part of a dialogue with citizens, including vulnerable, “undesirable” and marginalized groups, in order to guarantee them not only the access to public spaces, but also their involvement in planning and decision-making processes. Studies show that young people have a great potential to bring unique insights to the built environment. This chapter explores the potential of young people to be involved in placemaking, reflecting on challenges facing such involvement and taking into account the impact of the Covid-19 pandemic. Backed by studies in Cork, Lisbon, Ljubljana, Stockholm and Volos, it addresses the question how to use placemaking to change the city into a more inclusive and responsive environment for young people. These cases demonstrate that placemaking can be used as a tool for engaging young people in the decision-making process about their city and local environment, collating evidence-based research on the relationship between young people and public spaces.