The article presents and describes the methodology of the conservation of stone structures that are architectural monuments discovered as part of the work carried out during archaeological excavations in Tanais. The authors’ experiences presented in the article result from many years of cooperation between the Faculty of Civil Engineering at Warsaw University of Technology and the Antiquity of Southeastern Europe Research Centre at the University ofWarsaw. Examples of preserved masonry structures come from an excavation in Tanais near Rostov-on-Don. Works on stone structures located in the area of archaeological excavation are characterised by a unique specificity covering both formal issues, resulting from international standards and agreements regulating the conservation of historic buildings, as well as technical and environmental issues. The primary technical issues include ensuring the safety of further excavation works, protection of masonry structures against the destructive effects of atmospheric conditions and preparing the structure for possible exhibition in archaeological parks organized on the site of excavations. The article presents the procedures that should be used to conserve this type of structure and the specific sustainable technological and material solutions used in the shown objects.

Every conservation works related to an ancient masonry structures should be preceded by an appropriate diagnostic. This should be understood as geometrical survey and various tests, which results with a proper analysis of the structure, identification of materials, technologies and techniques used during construction. The effective tool which could be used in this field is 3-D laser scanning. The digital image obtained as a result of scanning could be a proper base for a preservation programme, as well as help for creation of a precise digital models for a structural analysis. The examples of 3-D laser scanning application presented in the article are diagnostic works carried by the Division of Fundamentals of Building, Warsaw University of Technology, with the cooperation of Warsaw University, at the archaeological sites in Alexandria, Egypt and in Tanais, Rostov, Russia. Based on this works some most important advantages of laser scanning in identification, diagnostics and preservation of ancient architectural monuments was stated.