In recent decades, the importance of the built environment and its resources has emerged as an issue, especially in countries with a moderate climate that wish to establish parks with limited conditions and resources (Ceballos-Lascurain, 1996). Parks should not be considered isolated structures, since they interact spatially, and are functional components of landscape ecosystems (Noss, 1987). Moreover, parks can be a source of many wider benefits, in- cluding purifying the air; providing water; improving urban micro-climates (Chiesura, 2004); minimizing stress, and enhancing meditation, thereby revitalizing city inhabitants; promoting a sense of peace and tranquility (Ulrich, 1981); extending the lifespan of elderly people (Takano et al., 2002); encouraging the use of outdoor space; increasing social integration and interaction among neighbours (Coley et al., 1997); mitigating the cost of pollution abatement; preventing and reducing the incidence of disease; attracting visitors and promoting a city as a tourist destination; and generating revenue and employment (Chiesura, 2004). As such, and for example, (Parés-Franzi et al., 2006) examined how the urban parks in Mediter- ranean cities are distributed, and assessed the ways in which their design and management follow criteria adapted to Mediterranean environmental conditions. The authors found that incorporating certain sustainable practices can significantly improve the environmental performance of these public spaces, under the conditions of a Mediter- ranean climate. Moreover, (Ayeghi & Ujang, 2017) explored the impact of the physical features of an urban park on their users’ attachment to the park, with reference to KLCC Park in Kuala Lumpur. They found that the physical features influenced the users’ functional attachment, and active features, such as water features, had a stronger effect on user attachment than passive features. Urban managers and urban designers are now able to create pleasing open spaces that attract increased numbers of visitors, due to their sustainable physical features. According to (Jim, 2000), there are two crucial aspects of sustainable landscape planning: providing high quality planting, and guarding against subsequent degradation and intrusion. In addition, (Tian et al., 2011) assessed the green space fragmentation in Hong Kong, and found that the fragmentation index took almost all of the characteristics of the landscape pattern into account, in terms of the size, shape, proximity, connectivity, heterogeneity, and interspersion. Meanwhile, (Maruani & Amit-Cohen, 2007) reviewed and compared a number of planning approaches and methods applied to open spaces, and illustrated the differences between these models, claiming that securing a satisfactory and dynamic design for open spaces cannot rely on planning alone, as it also requires a thorough understanding and control of local engineering bodies and stipulations that should be adhered to.

The Saudi environment possesses certain climatic challenges, since it is harsh and dry, and can be classified as BWh climate, with an average temperature above 18 °C (Weatheronline, 2019). The climate and culture are similar in Arabian countries, such as Saudi Arabia and Egypt, with the latter characterized by a hot, arid zone with variable day and night temperatures (Fathy, 1973). In addition, the challenge of water scarcity means that there is a reliance on non-renewable groundwater supplies to cope up with growing demand (Swain, 1998). Due to the increasing demand for water in the Gulf Coast Countries (GCC), where water resources are limited, alternative water sources are now sought, such as wastewater reclamation, and desalination (Al-Rashed & Sherif, 2000). According to (Sutton et al., 2009), Saudi Arabia accounts for 4.6 hectares of ecological footprint per person, which ranks the country among the most environmentally challenged countries in the world.

The Kingdom of Saudi Arabia (KSA) has therefore established national parks to motivate tourism, under the supervision of city councils, that are sustainably operated and maintained, employing renewable energy applications, and resource preservation measures. For example, Al-Baha city possesses a wide selection of green spaces. It is located in the region of Al-Baha, on the western coast of the KSA, and is affected by the Indian Ocean monsoons, with an average rainfall of 300 millimeters occurring between October and March, which constitutes approximately 60% of the annual precipitation (Weatheronline, 2019). Therefore, serious consideration was given to the develop-ment of the forests in the region (Tourism, 2004), in order to create guidelines and regulations to be implemented for their landscaping and sustainable long-term operation.

The present study reviews the planning and design considerations of national parks that are applied at the landscap- ing stage, and the coordination of these aspects, which together seek to achieve desirable optimum solutions that satisfy sustainable development principles. Sustainable parks depend on their design to attract tourists, therefore the design must promote the most effective bioclimatic level in which cost effective maintenance, and a visually pleasing appearance, can be achieved. In this context, it is necessary to consider several aspects: the conservation of limited resources; operational cost; waste reduction; prevention of air, water, and soil pollution; organic fertil- izing; the life cycle of the grass; organic pest control measures; the selection of suitable plants and trees that can adapt to the climate and location; and the efficiency of irrigation through the use of renewable energy technologies.

This study focuses on the sustainable elements of park planning, and discusses their roles, seeking to conclude a vision and standards for park landscaping that promotes sustainable built environment development, taking into account the majority of the sustainable principles, and applying them to the current design of Prince Meshari Park, Al-Baha city, Saudi Arabia, clarify their potential outcomes according to the current situation of the park.

This study assessed certain principles of sustainable design for park planning that contribute to the development of the built environment, and motivate ecotourism, by assessing those employed in projects, such as the Internationale Bauausstellung Emscher Park (IBA Emscher Park); the Internationale Architecture Exhibition Emscher Park in the German Ruhr region; KLCC Park in Kuala Lumpur, Malaysia; Horsetopia -Run Fast Live Slow, in South Korea; and Upcycle Park, in Hong Kong. The study also proposed a new design for the case study of Prince Meshari Park, in the KSA, applying sustainable concepts, and discussing the anticipated outcomes resulting from the new design.

Ecotourism is a form of tourism that is committed to enjoying the natural environment in a way that does not violate the ecosystem, or have a negative impact on the biodiversity. The ecotourist enjoys observing ecosystems, and their constituent animals and plants within their habitat, and also enjoys the historical, cultural, and heritage features that characterize the location. Compared with other forms of tourism, ecotourism tends to be more cultural, and less harmful to the environment, since it is green, responsible, and sustainable. As part of this, ecotourism is concerned with the landscaping of parks that contributes to the promotion of ecological balance, and has an interest in maintaining an environment free from pollution, and in improving the environment in general, including preserving the wildlife (Newman & Jennings, 2012). It should be emphasized that the importance of parks, both for tourism, and as a strategic reserve for natural resources and genetic banks, requires the support of governmental initiatives to provide the necessary scientific research and equipment to ensure the preservation of their resources. Ecotourism can contribute to the economy of the built environment if these parks are carefully designed (Al-Sawaf, 1992). As well as the benefits of their natural environment, parks offer many other attractive opportunities, including the ability to demonstrate the customs and traditions of local communities, and to produce publications, souvenirs, and television and radio programes, for example regarding the forest in the park and varieties of trees it includes. The integration of ecotourism into the Sustainable Parks Management Plan will contribute to generating a sustainable national income, and to raising awareness of the importance of preserving biodiversity and natural resources.

The Internationale Bauausstellung Emscher Park, Emscher Region, illustrated in Figure 4, Germany: This park was created in the 1980s as part of an initiative to promote urban development, and socio-cultural ecological measures as the basis for economic change in an old industrial region (I.B.A., 1999). As a principal contribution of the park initiative, its sustainable landscaping was critical for offering a new perspective on approaches to regeneration. The initiative was based within a framework that ensured the enhancement of biological requirements, and the well being of the local population, thereby eliminating the predominance of economic interests. However, the en- vironmental improvement was also deemed by the park’s planners to be a prerequisite for economic renewal, since business was becoming increasingly connected with environmental aspects. The approach applied to the park’s de- sign was appropriate to the principles of sustainability depicted in Figure 5, in which each factor contributes to the overall sustainability, as the environment should contribute to human welfare, the economy should be maintained at a suitable wealth level, and social choices and institutions should be sustained. The design concept of the park was embraced, as it employed brownfield, rather than greenfield sites to accommodate structural change, without requiring spatial growth; secondly, it embraced maintenance, modernization, re-use, and better building techniques to lengthen the life of the buildings and production facilities; and finally, it transformed the production structure in favour of environmentally sound products and manufacturing methods (Ganser, 1996).

KLCC Park Kuala Lumpur, Malaysia: The KLCC Park in Kuala Lumpur, Malaysia, was designed to illustrate the continuity of the country’s green, tropical heritage through the integration of human creativity. The design of the park is that of beauty and harmony in the bustling city centre, as illustrated in Figure 6. It was created in an area of 20 hectares, and designed by the late Brazilian landscape architect, Roberto Burle Marx, who employed assemblages of trees, shrubs, cement structures, natural stones, traditional Malaysian wood, and multi-static water, blending their shapes and textures with the topography to produce an attractive, state-of-the-art design. The lake was aesthetically designed to be the focus of the park, and to include a musical fountain. There is also a playground for children in an area of 2 hectares. In general terms, the park design provides three basic elements: geometrical formations created by the bodies and channels of water, with a bridge spanning the lake; aesthetic features, such as a dolphin statue made from chrome-clad steel; and planting that includes a range of trees in variety of colours that creates a natural consistency with the surrounding pillars, edging, and terraces (Elsayed, 2012).

Horsetopia -Run Fast Live Slow, South Korea: Horsetopia is a horse park in Yeongcheon, South Korea. Fifty percent of the 1,474,883 site is devoted to horse racing, while the rest hosts horse-related activities. The park adheres to sustainable principles, within its profit-based operation, and its design includes 100% path lighting powered by on-site wind turbines; 95% of the earth excavated reused on site; 450,000 tons of the carbon dioxide produced stored on site within the architecture; five layers of terraced bioswale to remove water pollutants; 45% of the total area reserved for landscaping, in the form of open parkland, to reduce the heat island effect; innovative lighting solutions to reduce light pollution; food grown on-site, and food waste processed on-site; and souvenirs made using food waste and horse waste. The project seeks to elevate the status of horse racing over the next 10 years. In addition, all of the architecture was designed as extension of the landscape, with the contours of the landscape exploited to create zones, and to define boundary-free green spaces. The racing track was designed as the focal point, with various features circling outward from the fast track to create 'slow' zones.

Upcycle Park, Hong Kong: Since it is located on the site of the old Kai Tak Airport, and its design includes the reuse of parts of old aeroplanes, Upcycle Park in Hong Kong seeks to play a role in entertainment, the economy, and ecotourism. Its contextual form was inspired by the master plan of Kowloon City airport, and it was designed to create an ecological environment suitable for various native species, with the design also respecting the airport’s history. Hence, the airport’s existing platforms serve as a bridge, a pool, and a stair above a canal, and simultaneously connect the surrounding structures into a holistic design. The park employs a multi-layered filtration system as a sustainable approach to watering, and several layers of terracing, incorporating a range of different plants, were built on both sides of the canal to filter the water runoff from the local neighborhood, purifying the water before returning it to the river. Some of the water is then exploited for recreational purposes in a pool. Repurposing the old structures constitutes an alternative approach to sustainable design, and includes reusing an old aeroplane as a canopy, bridge, tunnel, and outlook tower (Architects, 2019).

Prince Meshari Park, or ‘Al-Zaraieb Forest’, is located in the southwest of the KSA, between the nearby cities of Al-Baha and Al-Mandaq. The climate is moderate during the summer, and rainy in the winter. The forest is characterized by a wide and abundant variety of vegetation, such as acacia, pines, figs, and juniper. It has been developed in successive periods, and includes children’s play areas, family zones, lighting, internal vehicle tracks, and sports fields, as illustrated in Figure 9. However, the park currently requires an environmental management plan, in order to assess the current situation in detail, and provide recommendations to guide the future development of the forest. The plan requires the following elements:

In order to conduct these surveys and evaluations, a number of sites at the park were selected and evaluated, according to a set of systems that integrated planning and design principles, and therefore constituted a strategy for the development and sustainable coordination of parks.

The proposed sustainable design of the park allocates sites for different types of activities, such as festivals, sports, and aquatic playgrounds. It includes walkways for horses and bicycles, playgrounds for children, and seating zones, proposing that the park is divided into variety of different environments, including natural environments, a central garden environment, slope environments, and modern environments that can be employed for recreational structures. The landscaping considerations of these environments can be summarized as follows:

The concept of sustainable parks that the KSA has committed considerable effort to incorporating into new designs, planning, and landscaping must adhere to a variety of practices that respond to environmental issues in terms of their operational management and renewable energy applications. The design proposal for Prince Meshari Park represents a model of a sustainable park, and exemplifies the principles that must be considered when designing such spaces. These are as follows:

Furthermore, the International Organization for Standardization (ISO) standards for SMEs, industrial, commercial, and residential facilities should be adopted, as energy auditing is a significant factor that can play a key role in achieving energy efficiency, and reducing power consumption, a goal that is included in the KSA's 2030 national vision. Once the new primary energy tariffs are imposed, sustainable parks should optimize their energy usage without affecting their operation and processes, thereby maintaining their overheads and profits, while increasing their energy efficiency and competitiveness. For this reason, energy auditing should become a core requirement, rather than simply a popular trend, therefore technologies such as solar powered trash bin compactors, rainwater harvesting for parks and open spaces, and solar PV systems for energy generation should be adopted.