Low-density rural regions face major socio-economic problems, such as desertification, ageing, unemployment the decline of infrastructure. They are considered to be economically less productive and are often captured in downward spirals due to the loss of inhabitants, especially young and highly skilled people [1]. The depopulation of rural areas has intensified since the mid-1950s in many European countries [2] and Portugal is not an exception [3]. Molinero [4,5] introduces the concept of “deep rural” areas to characterize these territories that have low population densities and are suffering from depopulation. Several economic factors are behind the depopulation trend, namely, those related to the lack of employment and business opportunities. Combating this trend requires the design of appropriate policies, which are often difficult to design and implement, to promote the sustainable development of low-density rural regions, particularly those affected by depopulation [2,6].

Since the late 1970s, scholars have made pleas for endogenous initiatives for the local socio-economic development of these territories, with growth based on home-grown assets and resources (e.g., natural resources, human capital, historically rooted skills and local business culture and traditions) [7,8]. More recently, and notably since the beginning of the 2010s, a paradigm shift has happened, with the emergence of the neo-endogenous development theory, which adds the idea that the development of any territory is both influenced by and dependent on the wider context in which it is embedded [6]. This entry adopts this perspective and understands rural development as a process that calls for the interaction between the endogenous knowledge and resources (available within the region) and the non-local knowledge and resources required for the development [9,10]. This perspective is in line with the place-based regional policy approach, which considers regional development to not be limited to endogenous development policies of local inspiration, but rather to include endogenous and exogenous dimensions, with the territory as the centrepiece of public policies, and the interaction of actors and institutions at several governance levels [11].

Until the 1960s, rural areas were mainly seen as spaces dominated by traditional agroforestry activities. Since then, other activities have gained expression, namely, landscape protection and a wide set of activities that respect the environment and its natural resources [12]. In fact, extant research has described a trend towards multifunctional agriculture in Europe [13], with a diversification in farmers’ activities, namely, by including tourism, biomass production, nature and landscape management and educational activities [14]. Nowadays, rural areas are also seen as spaces of multifunctional consumption, including leisure and recreation [15]. This multifunctionality of the rural territories can bring new opportunities for deep rural areas, which are usually dominated by agrarian activities [4]. Still, farmers’ livelihoods and rural development are closely related, as most of the rural populations still depend on agroforestry for their livelihoods. Resilient EU farmer livelihoods and the rural communities they support are crucial in the transition to sustainable systems [16].

Some scholars have been stressing the role of the development of new business models (BMs) in agroforestry and tourism activities, as part of an inclusive and sustainable approach, as an effective economic driver in the structurally weak low-density rural regions [17,18]. This would enable them to attract people and new business to the region and to promote its sustainable development, a concept that integrates the social, economic and environmental spheres [19].

Sustainable development in low-density regions that are largely dependent on agroforestry systems raises significant challenges [20]. Farmers need to innovate in several dimensions to create and implement new practices; to adapt to legislative, policy, market and environmental changes; to market their products; and to take part in collaborative processes. In this context, entrepreneurial initiatives may promote several types of innovations, helping rural areas to develop better and overcome the challenges they face [21,22]. Technological innovation, and, particularly, the use of digital technologies, is considered to be important in this process by promoting connectivity in the agri-food system and reducing inefficiencies in the value chain, with an impact on farmers’ incomes and increasing the sustainability of the system [23]. Social innovation, i.e., a process of social change that involves the empowerment of actors and the emergence of new ways of doing, organizing, knowing and framing [24], that contributes to the building of more sustainable, resilient and inclusive societies [25] is also increasingly considered to be important for the development of low-density rural territories [26,27], namely, under the neo-endogenous development approach [10]. Likewise, the literature is gradually stressing the need to introduce new practices that are based on new models of production and consumption, namely, regenerative agriculture and circular business models [28,29].

These changes (diversification, innovation and sustainability) demand the development of farmers’ entrepreneurial and organisational skills. Farms in Europe tend to be small and medium enterprises that face a set of constraints in terms of financial, human and social resources, hindering their capability to successfully change [30,31,32]. Networks (including informal contacts and formal partnerships) with a wide set of actors, namely, businesses from related sectors such as tourism and handicraft production, but also local authorities and communities, are considered to be important mechanisms for overcoming such constrains [33,34]. Accordingly, scholars progressively adopt a systematic approach to study innovation in rural contexts, where firms (e.g., farmers) interact with other stakeholders in multi-actor, multilevel systems to introduce change and promote local development [17,21].

In the mid-1980s, it was argued that tourism in rural communities was one of the most appropriate options for the development of rural populations [35]. It is an activity that reconciles social equity and the preservation of natural and cultural heritage, without endangering future generations [36]. It is, therefore, a proposal of sustainability and local management in rural environments. Currently, the rural environment has come to be seen as an area that offers experiences related to rest, leisure and safety. Thus, it is interpreted through two prisms: as a tourist offer, by its local management, and as tourist demand, by travellers looking for new experiences [37].

Currently, tourism has an important impact on rural areas and livelihoods [38], since these areas have become attractive tourism destinations due to their landscape characteristics, which are based on rurality, traditional culture and history and natural attributes [39].

Several rural areas in Portugal are considered to be tourism destinations, despite being in an emergent phase but showing a great capacity for evolution and affirmation given their specific and distinctive characteristics [40]. This growing importance of tourism in rural areas was the result of European policies launched during the 1990s and 2000s, with the ultimate objective being to relaunch economic activity in these areas and turning them into multi-functional places [39,41]. Tourism and leisure services have been, thus, considered to be activities that are complementary to traditional agriculture practices that will help to arrest decline [41]. Even in these last years of the COVID-19 pandemic, when the tourism sector has suffered a significant decrease, these low-density rural areas have “suffered a less severe impact on tourism demand, and domestic tourism was able to mitigate some negative effect” ([42], p. 1). At the current juncture, rural tourism has the components to consolidate itself as a viable alternative for tourists by not generating crowds and developing in open and safe spaces [43].

However, the growth of tourism in these areas requires to balance the dynamic tension that characterizes the relationship between tourism development and the protection of the territory and its landscape [44], since tourism may impact negatively on natural and cultural resources [45].

New approaches to heritage management should be directed towards the sustainable development of local communities. One of these approaches, which has produced very interesting results, is the so-called working with people (WWP) model [46] for revitalizing rural areas through rural tourism, which has been mostly experimentally applied in Ayacucho (Argentina) [47].

These new approaches also advocate for the involvement of local people in the development of heritage management plans, since this will raise the awareness of residents to heritage value and contribute towards the sustainable protection of sites [8,48]. They also stress the need to consider the tourist experience in the management of heritage sites “to achieve the goal of sustainable heritage tourism” ([49], p. 269).

Although natural and cultural resources are the main attractions of a territory and the basis of its competitive advantage and endogenous growth, it is essential to take into account the way these resources are incorporated into qualified tourism products to satisfy the needs and expectations of tourist demand [50]. Thus, it is essential to have satisfied tourists and involved stakeholders to achieve sustainability in these heritage sites [49]. The sustainable management of natural and cultural heritage sites requires conciliation between conservation and the new economic and social function triggered by tourism. The practice of responsible tourism is essential, and the good use of heritage is the best guarantee of its conservation [51]. Providing accessibility to heritage sites is considered to be a way to promote the sustainable management of those regions. The concept of accessibility is usually characterized by physical and architectural aspects—space accessibility—but it goes much further, as it also concerns the accessibility of information, social, intellectual and emotional components. It means that all people, with or without special needs, must be able to participate in all activities that include the use of products, services or information [52,53].

Accessible, universal, inclusive or barrier-free tourism can be defined as tourism and travel accessible to all people, disabled or not, who may present temporary or permanent limitations concerning mobility, hearing, sight, cognitive, intellectual or psychosocial limitations [54,55]. It is associated with a way of thinking, planning and managing a specific destination, region or place. An accessible destination should allow all visitors, without exception, to enjoy and use equipment and services, without restrictions or constraints, in an equitable way.