The reaserch paper deals with Sustainable Urban regeneration of historical city centers and focus on the the physical regeneration which is represented in Public Realm considered as a social interactions nodes and cultural vibrant, as Public Realm is a group of spaces which reshaped by local community.

The main trend of world heritage organizations such as the English Heritage and the Aga Khan Foundation is to develop the urban regeneration strategies for the historic core. Urban regeneration of public realm of historical city centers greatly contributes to improving the quality of Urban environment, (Urban, public and private buildings, services, infrastructure, traffic systems, green areas and open spaces, all urban areas and skylines), as well as the commitment of stakeholders at various levels (local, national, and international), with the strategic objectives of the city and the regional economy, thereby increasing business, economic opportunities . Footnote 12

In accordance with the Aghakhan Development Historical Cities Report 2011 where Urban regeneration of historical city centers was defined as a comprehensive, integrated vision and action plan that addresses the urbanization, economic, social, and environmental development of target areas , Urban regeneration of historical centers is intended to change the nature of the place by involving the local community and stakeholders by creating an agenda of goals and activities. The main components of Urban Regeneration as illustrated in Figure 1, are (Physical regeneration – Environmental regeneration – Economic regeneration – Socail regenration).

The dimensions of sustainable development as illustrated in Figure 2 that affect the process of urban regeneration are divided into a number of dimensions, namely economic dimensions, human / social dimensions, environmental dimensions and their reflection on urbanization technology. The dimensions of sustainable development are detailed as follows:

- Economic Dimensions:

The sustainability of developing countries is increasing the use of resources to improve living standards, because there are a direct relation between poverty, environmental degradation and rapid population growth. Sustainable development means for all countries: to reduce the growing disparity in income and access to health care, education, social services, natural resources and political rights equally of society

- Human / social dimensions:

"Social development" means the human / social dimensions, the population and the community of the target areas, where "sustainable development" from the social perspective means making significant progress in stabilizing population growth, because the rapid growth of the population places severe pressure on natural resources and the ability of governments to provide services.

- Environmental Dimensions and their Reflection on Urbanization Technology:

Sustainable development in terms of the environmental dimension and the technology of urbanization also means the transition - especially industrial countries - to cleaner and more efficient technologies, to minimize energy.

Figure 2

Public realm is a public-owned areas of streets, squares, green areas, public parks, pedestrian paths, buildings, public facilities, all urban spaces and public uses that meet the needs of all individuals in different segments of the society.

Attempts to define the attributes of the public realm and according to Abu Dhabi Urban Planning Council , Public realm includes all outdoor areas that are visually accessible regardless of ownership. These elements can include: streets, bicycle paths, pedestrian routes, public squares, nodes, transport axes, garden gates, waterfront, natural landmarks, And facades of buildings. Public areas are divided into four categories as illustrated in Figure 3.

The heritage heart is divided into a group of public spaces network: (motorways neywork, pedestrian paths, the squares and the green network. These networks range from the main level to the sub-level in a way that works on the historic interconnection.Footnote 14

According to urban regeneration strategy of the historical heart of Birmingham City, the public spaces network was divided as illustrated in Figure 4.

Public realm network of historic city centers consists of three networks: Vehicles network, Pedestrian Routes network, Public spaces network. Each of these networks is divided into several levels as followsFootnote 11 : A - Vehicles network: The streets network of vehicles is divided into two main levels: -First level: the main streets: The streets of the movement of vehicles surround the historical heart, and is an entrance to the inner area of the heart of the center, the main public streets and a lane dedicated to public transport buses and super tram. - Second level: the secondary streets: The network of the streets of the vehicles from the main streets to the secondary streets, serving the heart of the center from the inside, and move the movement from the outside to the center, which does not affect the network of pedestrian traffic. B- Pedestrian Routes network: Pedestrian Routes is divided into three main levels: - First level Major routes: It is the main route network for pedestrians, connected to the main street network of cars, and is a major network of historical heritage sites. - Level 2 Connecting Routes: It provides an alternative shred routes network, and is a subnetwork of the historical core heritage sites. - Level 3 Minor Connecting Routes: It is a pedestrian network, a narrow local street that reflects the sense of place, Heritage, and a distinctive architectural experience for visitors and residents. As shown in the figure 5.

C - Public spaces network: Public spaces network is divided into several types according to their purpose. There is a space that is intended to be a destination, a goal and another space that is an area for arrival or departure. The network of public spaces is as follows: - Arrival / Departure Spaces: Arrival / departure spaces have been for temporary presence and not destination or goal, usually called a drop off, pick up, and it must include parking spaces, signs and explanatory signs. - Meeting Points: Meeting Points are the main public areas and ranges of hiking with its various activities and distinctive tourist attractions as illustrated in Figure 5.

- Intimate spaces: These spaces are characterized by smaller proportions and sizes than the public squares. They are known as those spaces that are formed between the buildings and are characterized by an intimate character. These spaces are characterized by local activities such as cafes (as shown in Figure 6), which shows one of the intimate spaces of the city Birmingham.

The importance of "Rashid" in its geographical location, and its history. Rachid extension of the city, "Paulitin", was called "Rashit" in the Coptic era. Moreover, Rashid is distinctive in the Ottoman era, where it is the second city - after Cairo - in terms of the number of Islamic monuments; the city contains 22 houses with a distinctive Ottoman architectural style (as shown in Figure 7), and 11 historical mosques such as (the northern gate, the castle, the historic bathroom, and the Abu Shahin mill). The historical core of Rashid is the traditional heart of the harmonious urban texture.Footnote 10

By analyzing the current situation of Rashid public realm features (Corniche, streets , squares, and public parks) in the heritage heart of the city of Rashid as follows (10) Footnote 9

The results are divided into two main sectors: the physical dimension of urban reconstruction, and the non-physical dimensions of urban reconstruction,( Socio Economic and Social dimensions), as follows: