Principles of Demarcating Russian State Borders in the XVIII–XIX сenturies

This article presents the history of one of the Russian military fortresses of the XIX centurythe Aktau Fortification, built in the Kazakh steppes.The fort stands out due to its unusual shape, layout, and location far from the main Russian defensive line constructed in the XVIII-XIX centuries along the northern and eastern borders of Kazakh nomadic territories.The purpose of the article is to reveal the functional role of military fortifications in the expansion and consolidation of Russian state borders, as well as in the creation and maintenance of transit trade routes from Eastern Europe to the Near and Central Asia.The research objectives are: to show the Russian Empire's experience in colonizing new territories through the construction of military fortification lines; to explain the selection of the central Kazakh steppes as the site for the Aktau fortification; to demonstrate the level of military engineering from the XVIII to the early XX centuries; to examine the role of military fortresses in promoting Russian trade capital in Central Asian lands; and to provide a brief archaeological description of the site as a historical and cultural heritage monument.The article employs the chronological method for describing specific historical events, as well as the reconstructive method that complements standard Russian military projects with elements of steppe military architecture.Typological, cartographic, and structural analysis methods are also used to enhance material perception.Innovative approaches include GIS methods and digital technologies used to interpret dimensional data from satellite and photo imagery of landscape-preserved structures.As a result of studying the history of the Aktau fortification, the reasons for its construction and eventual decline have been reconstructed.Archival scientific and governmental documents from the XVIII to the XX centuries provide insight into how fortresses were used in asserting and consolidating Russian authority in the Asian territories of the empire.