The surrounding plazas of heritage mosques are considered an integral part of the identity of these mosques, where many historical layers have been accumulated. Therefore, these plazas were a witness to successive civilizations and events. It is an element of understanding the heritage domain and its surroundings. The plazas are not only areas to access or transit to the mosque but are considered a major area and a vital facility for movement, interaction, communication, and the practice of religious rituals and customs.The aesthetic design of the city begins with the creative and successful artistic and design formation of its squares, especially squares of heritage character. Studying, analyzing, and applying the visual and aesthetic determinants precisely leads to the creation of a design that raises the efficiency of the entire site and the city in general. Moreover, we are working on the integrative study in all aspects of engineering and aesthetically (urban planning, design process). Paying attention to the required details and the elements that make distinctive plazas in order to be suitable with the general aesthetic form. These successful examples are clearly and distinctly seen in the plazas and squares of many western cities.  A large number of the old mosque plazas, particularly those in Islamic Cairo's neighborhoods, are dilapidated. Over time, they have experienced arbitrary events and modifications that have diminished their worth and capabilities. The majority of these historic plazas' maintenance and repair plans follow particular, conventional methods and policies. These plans frequently conflict with and have a detrimental impact on the standards of heritage development and preservation. Furthermore, they do not specify design concepts that are appropriate for certain locations. The responsibilities of the planner and the designer are not integrated together. Establishing a cooperative framework that allows them to set up design principles for those unique places and support creative visual vision. Human behaviors and activities are essential components of heritage sites and are among the components of urban legacy that are distinguished by artistic and cultural richness. Research Importance: The interest in studying the possibilities of the aesthetical heritage plazas and the extent of their integration with the functional side, create an integration in the general visual composition of the place. It is one of the important things that must be taken into consideration when undertaking heritage development projects, especially, when there is not enough attention and the lack of the aesthetic component is reflected in its deterioration.  These spaces consist of visual and visual determinants and coordination elements that cannot be ignored and take them into account which achieve comfort and safety for its users, and emphasize the role of applied art functionally and aesthetically. The process of designing these spaces is no different from designing any artwork. It will also help in avoiding the existing random and bad practices that disturb residents and visitors, which distorts and reduces the value and quality of the place. This, in turn, will add a great benefit to various fields, such as the field of religious tourism, and will enhance it positively. These heritage mosques are a great national and religious wealth, and they are a destination for visits from various parts of the earth, so they need an innovative vision commensurate with their sanctity. Research problem: Many of these plazas belonging to ancient mosques, especially those in the neighborhoods of (Islamic Cairo) are in poor condition and have been affected over time by random developments and changes. Therefore, their spaces and functionality have been reduced over time. We find that most of the maintenance and renovations of these historical plazas have a specific and traditional method and policy, which often contradict the standards of preservation and development of heritage and are negatively affected by it. There is no integration between the roles of the designer and the planner to work on finding a joint cooperation system between them to reach planning and design principles that highlight the distinct style of those sites and complement the visual vision in a balanced manner. While the heritage sites are among the elements of the urban heritage that are characterized by artistic and cultural richness due to their association with the various human behavior and activities. The problem of developing heritage areas is a global problem, as it has been negatively affected by developments and changes worldwide. These prompted specialists in the developed world and many concerned parties to create international charters, standards, and guidelines to take care of these heritage areas and work to preserve and develop them to become an important part of their urban development plans. Research Objectives: The objectives of the study are divided into the following objectives: 1- Clarify the importance of preserving these historical plazas. • Supporting the historical value of these places by transmitting cultural and civilizational meanings across generations. • Protection of these heritage sites from the factors of deterioration. 2- Functional design which is concerned with developing a design vision and a design program that highlights the role of these plazas and makes use of them: • Activating the role of the visual aesthetic elements for the physical and visual users that emphasize the characteristics of the place and facilitate its use. • Paying attention to the invisible needs of users, such as psychological, physiological and spiritual needs. Hypothesis: The research aims to confirm that the interest and upgrading of these plazas through innovative designs and advanced policies will reflect positively and contribute significantly to raising the quality of the place and improving the quality of life of the users, residents in addition to preserving heritage Results: Plazas around the world are different from one region to another due to their cultural and historical context. Therefore, their problems are different. Developing heritage areas is a global problem because developments and changes worldwide have negatively affected these sites. These prompted specialists in the developed world and many concerned parties to create international standards, and guidelines to take care of these heritage areas.