The notion of conservation evolved throughout history and gained different meanings in different geographies. Alt7 hough conservation has a long history as an action, its emergence as a theoretical field dates back to the nineteenth century. The concept of conservation has been transformed with the different meanings that major concepts such as time, history and memory have acquired over time. The theory of values developed by Alois Riegl in "The Cult of the Modern Monument: Its Nature and Origin,” (1903) opened a different channel in conservation studies. It is a theory that provides answers to the questions of which monuments should be preserved and how.

The conservation consciousness that emerged in the Renaissance is based on the centuries7long "The Quarrel of the Ancients and Moderns" in literature and art in Europe and the Renaissance’s transition from a cyclical or theological concept of time to an irreversible, progressive concept of time. The periodization of antiquity, the Middle Ages and modern times is made in the early Renaissance period and antiquity is defined as resplendent light, the Middle Ages as the Dark Ages and the Renaissance as the awakening from darkness, rebirth. In this framework, the renaissance ignores the Middle Ages in a sense, emphasizing Classical Antiquity and defining themselves as modern dwarfs on the shoulders of ancient giants. This, in turn, led to the study of Classical Antiquity, especially in Italy, during the Renaissance period, and the formation of a conservation consciousness in this framework.

The transition period from the 19th to the 20th century was such a period that the moderns considered themselves superior to antiquity from the 17th century onwards, and that they no longer had ancient giants to stand on their shoulders; at the same time, tradition and social structures were questioned and shattered, and all grounds that could form a basis were destroyed. Perhaps the only point that can provide a basis is the desire of the nation7states that emerged in the process of modernization to construct a historical past that will prove themselves on the world stage. Therefore, for every nation7state, monuments symbolizing these historical values are important and worth preserving. In such a transitional period, Riegl’s text is important in that it not only provides rational definitions and classifications but also proposes a system of values that can include singular examples and cannot be reduced to mere physicality. Its inclusive theoretical infrastructure is also valuable in that this system of values has the possibility of being developed. 

In Vienna at the end of the 19th century, unlike German art historians who based their understanding of history on Hegel’s philosophy, the work of historians approaching Hegel from a distance highlighted the prominence of rationalism, positivism, and empiricism derived from Enlightenment thought. At the same time, Friedrich Nietzsche’s critiques of Enlightenment thought were being followed, and debates on "Philosophical Irrationalism" were also occurring in the Viennese art historical context. Consequently, the rational understanding brought by Enlightenment thought, alongside the questioning of this rational understanding, created an environment that allowed for the emergence of diverse perspectives within the field of art history. 

Riegl entered this multi7faceted environment in 1880 by joining the Austrian Institute for Historical Research, one of the prominent institutions of the Austrian Empire. At the time Riegl joined the institute, efforts were underway to apply scientific methods to art history and to construct a new art historical framework in this context. Moriz Tausing, who was in charge during this period, directed these efforts while advocating for the necessity of art history finding its own intellectual and autonomous academic methodology. Both Tausing and Riegl prioritized the physicality of the art object rather than seeking the source of the art historical method externally. This understanding seems to have influenced Riegl’s recognition of the significance of changes over time in objects and, consequently, his formulation of the theory of the value of age.

While following rationality in the sense of "historical objectivity," Riegl integrated discussions of temporality and individuality into his efforts to preserve, demonstrating a non7reductive approach. Riegl advocated an understanding of objectivity based not only on the physical characteristics of objects but also on perceptual psychology and phenomenology. Therefore, Riegl was interested not only in the physical characteristics of monuments but also in how individuals perceived them. This understanding forms a significant pillar of his work The Modern Cult of Monuments. 

The most distinctive feature of modernity is the concept of "progressive, linear time." Riegl’s understanding of time forms the foundation of his value theory. He identifies two key conceptions of time: first, “time as a historical concept,” and second, “time as a phenomenon embedded in artifacts.” In the first conception, Riegl acknowledges the linear progression of modern time. In the second, he emphasizes the notions of temporality and continuity. According to Riegl, an art historian must grasp the interplay between these different perspectives on time—fluid and transient on one hand, and linear7interactive on the other. Another significant aspect of Riegl’s understanding of time is its connection to the concept of nature. For him, development signifies “continuous change or oscillation,” but not necessarily progress toward perfection. Riegl argues that science demonstrates how everything inevitably moves toward decay. This perspective challenges the modern notion of progressive time rooted in Enlightenment thought. In the late 19th century, when the concept of progressive time was a central tenet in Europe despite widespread upheaval, Riegl emphasized the primacy of natural processes. 

Riegl’s system of values involves the questioning of the commemorative value. In this theory, there are two main categories: commemorative values and present7day values. Commemorative values include age value, historical value and intended commemorative value; present7day values include use value and art value. The distinguishing feature of Riegl’s theory is the age value. In “The Cult of the Modern Monument,” Riegl discusses the aforementioned values compared with each other, but mostly with the age value, because the age value can contradict other values.

Riegl defines the age value with reference to different concepts: "imperfection, closure and lack of completeness," "deterioration," "disintegration," "disintegration into fragments," "reassembly of the singularity into its elements," "unification with formless nature." This idea, which also includes Riegl’s view of the concept of time, is based on the "pure, legitimate cycle of becoming and passing away" of nature in general. According to him, while a work of art is produced in a completed form by moving from parts to the whole, it returns to nature by disintegrating and dispersing after its incarnation. When talking about the age value of a monument, he also refers to the "unmistakable perception of the traces" of this dissolution.

In Riegl’s theory, historical value refers to a "singular" stage in the creation of a monument as a whole. It is a value that does not include deterioration and seeks and prioritizes completion. According to Riegl, "the higher the historical value, the lower the age value." For Riegl, who believes in historical continuity, the singular moment symbolized in the understanding of historical value is more important than the development itself. It is an understanding that freezes time, emphasizes the period in which the monument was produced and attributes a special importance to this period.

Intended commemorative value, on the other hand, focuses on not letting a moment identified at the time of the monument’s construction pass and keeping it alive and current in the minds of future generations. As the value with the highest demand for restoration, the intended commemorative value is the "mortal enemy" of age value. According to Riegl, the age value is based on extinction, while the historical value wishes to stop extinction. The intended commemorative value, on the other hand, "lays claim to immortality, an eternal present, and an uninterrupted becoming." 

Riegl exposes the contradictions of these three different categories of value and questions whether they can co7 exist. Although the historical value and the value of the intended commemorative value are almost diametrically opposed to the age value, he emphasizes that these values can be reconciled through individual examples, but that the age value should be prioritized. 

In this study, within the framework of Riegl’s values theory, it is analyzed which values come to the forefront and which conservation processes are realized in the re7functionalized seven prison buildings in Turkey. In the analyzed examples, it has been concluded that Riegl's commemorative value comes to the forefront, but other values, especially age value, should also be activated in the conservation process of a building. In the future conservation processes of the 378 abandoned prison buildings in Turkey, it is suggested to take into consideration the values theory, which will be important in terms of both the place of the buildings in collective memory and the continuity of their physical structures.