Results and discussion
Environmental aesthetics is the experience of understanding the environment through the examination and study of the perceptual quality of space, a space that is not merely visual. Valuable urban spaces from an environmental aesthetics perspective include: Exposure to nature, the presence of sustainable plants, the absence of traffic and noise pollution, the presence of natural places, the preservation of natural resources, creating a positive feeling in the individual by observing hygiene and cleanliness, inducing a sense of peace, arousing a sense of aesthetics, spatial organization such as clarity and lighting, coordination and organization of elements, appropriate location, attention to social and historical characteristics. In addition, there have been bans in various countries under the name of urban aesthetic control, including; Signage restrictions, height restrictions, overall coordination of buildings, off-street parking and loading areas, specific landscape elements required, percentage of open space required, Review of volume and mass, materials and texture, color and finish, style and character, maximum and minimum building and parking lot sizes, visual regulations, air pollution, underground utility requirements, percentage of site designated for landscaping, silhouette or cross-section review, facade clarity review, public art, etc. Environmental aesthetics is the experience of understanding the environment through the examination and study of the perceptual quality of space, a space that is not merely visual. Analyzing the meaning of symbols in an image can make the transmission of graphic design information more scientific, more precise, and increase the expression techniques that are applicable in the field of artistic creation and graphic design and play a vital role in culture and information between people. Symbols in semiotics are systematic symbols that people use to convey meaning. A symbol in graphic design, as a non-verbal sign, has many similarities to linguistic symbols. Patterns contain symbols and act as a powerful medium for expressing cultural identity, religious values, and geographical diversity. The feeling of security in urban spaces is considered one of the most important indicators of the quality of space, and conversely, the feeling of insecurity and the concerns arising from it overshadow other human activities. Although security is a complex issue with diverse and numerous socio-economic and cultural dimensions, the role and impact of environmental factors should not be overlooked in ensuring this. Security has always been considered one of the most fundamental needs and one of the main factors in the sustainability of human societies, and with the increasing complexity of societies, the conditions for providing and resolving it have also become more complex.

Conclusion
As a sample, 12 urban graphic works of Mashhad and the motifs used in them were examined and studied, based on the type of motif, to the extent possible and the time allowed for discussion. The results of this study show that there are many commonalities between pre-Islamic and post-Islamic motifs in Iran. Based on the research objectives, the history of the formation of motifs in Iran is classified into early motifs, ancient motifs, and Islamic motifs, and the motifs used in the graphics of Mashhad can be classified into various types: plant, human, animal, abstract, composite, written, and geometric motifs. The present study explains that the images used in Mashhad's urban graphic works are not used solely for decoration, and the majority of them have a valuable historical and cultural background in Iran, so that one can understand the fascinating roots and significant connection of prehistoric images with Islamic images. In addition, the presence of the shrine of Imam Reza (AS) and the proximity of Ferdowsi's tomb, etc., have a significant impact on the selection of content and concepts of Mashhad's urban art. In response to the third question, the results indicate the significant role of cultural, artistic, economic, and social security of urban spaces in the creation and protection of urban graphic works and the transmission of the concepts of Iranian motifs before and after Islam to other generations. Environmental graphic works, as signs of visual language in messaging, convey the message to the audience in the shortest possible time. In the foundations of urban aesthetics, the most important factors in the value of urban spaces are the presence of valuable works of art, safety and security, and the manifestation of cultural, social, and historical characteristics in urban spaces, which increase the aesthetic values of the city, as well as improving the visual level of urban spaces and creating interactive and memorable spaces that have a significant impact on the audience.