**5. The links between urban renewal and sustainability**

Especially in the early developed cities, urban areas grow and deteriorate as time goes by, and adversely changing conditions of the environment make life miserable for the people living in them. So urban renewal projects to improve the built environment take place [20]. Emphasizing the importance of sustainability in this context, Bai et al. [21] argue that 'the battle for sustain‐ ability will be won or lost'.

In general, urban land is both precious and scarce, like some other sources. Thus, the main objective of urban planning is providing reuse of the already scarce urban sources taking into account the public interest [12]. To do so, urban planning should be obliged to enable the public interest principle, and establish and apply necessary rules reconciling private interests with the public interest depending on the character of the economic structure and political regime of every country [5].

Nevertheless, decisions on the future of cities should be taken with the participation of the relevant stakeholders mainly consisting of the state sector, local government sector, private sector, civil society organisations, local residents as well as academics. In this context, a sustainable urban renewal strategy should take into consideration the entire life cycle of urban structures from design and construction to the operation and maintenance as well as life quality of the residents [8].

Finally, as a living organism, the city is a hybrid system consisting of structures with natural areas. But, rapid and unplanned urbanisation is the biggest threat in terms of the sustainability of the natural and cultural sites. According to Sancar, technical infrastructure and transporta‐ tion are extremely important for sustainable organisation and also decisive in terms of the quality of urban life [22]. The adequacy or quality of the technical infrastructure is considered to be among the issues to be addressed first. In addition, transportation systems of the vehicles and pedestrian in the city need to be re-evaluated within the understanding of a holistic planning approach in order to achieve the goal of sustainable urbanisation.
