An Investigation of the Strategies of passive defense in the Spatial Organization and Architecture Features of the old Mourcheh Khort Citadel

Passive defense in architecture and urban planning was formed based on the defense strategies of human societies. Passive defense includes principles that increase the defensive power of societies and reduce the vulnerability of humans, buildings, and facilities to crises. Today, the principles of passive defense were changed due to the development of societies and the transformation of dangers. But some of the principles that were conceived in historical periods for the design of cities, villages, and architectural elements have in common with today's principles of passive defense. These principles were also used in the old Mourcheh Khort Citadel. This citadel, as one of the vast and complete historical contexts, makes it possible to study the principles of passive defense in the Islamic period. The questions are: what are the passive defense measures in the old Mourcheh Khort Citadel? How have these measures affected the spatial organization and architectural elements of the Mourcheh Khort Citadel? The purpose of this article is to explain the principles of passive defense in the design of the spatial organization and the architectural elements of the old Mourcheh Khort citadel as one of the most prominent and enduring examples of historical monuments in central Iran. The architectural features of Mourcheh Khort citadel were collected in the archaeological field survey of the citadel in 2009 and 2017 and then, these features were documented. Data related to the principles of passive defense were also obtained through documentary methods. This research as a qualitative research was done in a descriptive-analytical method. Then, data analysis was performed separately for the spatial organization and architectural features. The results show that the spatial organization of the old Mourcheh Khort citadel was influenced by factors such as the ease of meeting vital needs during natural and unnatural hazards, the decentralized design of residential quarters, the enclosed and defensive elements, and the creation of escape routes. winding passages leading to dead ends is an example of the principle of deception in the spatial organization of the citadel. In terms of the characteristics of the architectural elements, some measures were considered, such as angled access to the spaces, a room above the entrances to control the movement of people, gated and dead-end alleys, the lower floor level of the yard, windows, and doors in high elevations, and strengthening of buildings through connection and proximity of structures to reduce vulnerability and maintain the safety of residents in the old Mourcheh Khort citadel. Introversion and simple facades are examples of the principle of deception in architectural features. Also, features such as hiding places, angled entrances, and the same color of the materials with the environment are examples of the covering principles in the architectural features of the old Mourcheh Khort citadel.