Defensive Architecture of Fortresses in Ancient Khorezm: A Comparative Analysis of Ayaz-Kala I, Burly-Kala and Kyzyl-Kala

This article compares three fortresses of Ancient Khorezm located in the north-eastern part of the Lower Amu Darya basin — Ayaz-kala I, Burly-kala and Kyzyl-kala — using published descriptions of their fortifications, research history and stratigraphic observations. The aim is to identify common design principles, differences in plan, scale and function, and the main gaps in the chronology. All three sites share a double-wall scheme with an intramural corridor, but they differ markedly: the corridor of Ayaz-kala I is a blind vaulted passage without loopholes, whereas Burly-kala and Kyzyl-kala have loopholes in the outer wall; the area of Ayaz-kala I (c. 2.8 ha) is about seven times that of Kyzyl-kala (c. 0.4 ha). At Burly-kala, the cultural layer sealing the loopholes and later additions to the walls and gate document a change from a fortress to an unfortified settlement in the 1st century AD. The published chronology covers broad ranges (4th century BC – 4th century AD) and, in the sources reviewed, is not supported by radiocarbon dates. A programme of sealed-context sampling, geophysical survey of the interiors and 3D documentation is proposed.