Natural stones have been used for thousands of years as one of the oldest building materials. The most fundamental problem in the construction and restoration of historical monuments has been the provision of stone materials. This difficulty in stone supply has made quarries with marine transport more important. In this context, on both sides of the Gulf of Izmit, the quarries that met the stone needs of Istanbul and its immediate surroundings have been in intensive activities. The use of local material resources in the supply of materials closest to the original material is also important in terms of making repairs in a sustainable approach to the historical artifacts. Aim: In this study, the availability of natural stone materials used in historical monuments around Kocaeli and Istanbul from Kocaeli and its immediate surroundings will be investigated. Method: As a result of literature survey, information obtained on stone types, quarry places and historical artifacts have been used. Results: It is known that Kocaeli is an industrial city, has a rich potential for the local building material availability but it has been found that due to the formation of new settlement and industrial areas these potential areas can not be used very actively. Conclusion: It is understood the importance of planning the establishment areas such as settlement and industry under consideration of the conservation of natural resources in the planning of the cities. It is considered useful to update the inventories obtained from the previous studies and to integrate them into the study of “Natural Stone Information System” (Erkanol and Aydındağ, 2013: 174-156) for the accessibility of the original or the most suitable stone product which can be used in historical works for restoration.
Keywords: Kocaeli, Local Building Materials, Natural Stone, Sustainability