Brief synthesisVisible from great distances in the surrounding lowlands near the ancient Ziyarid capital, Jorjan, the 53-metre high Gonbad-e Qābus tower dominates the town laid out around its base in the early 20th century. Criterion (i): Gonbad-e Qābus is a masterpiece and outstanding achievement in early Islamic brick architecture due to the structural and aesthetic qualities of its specific geometry. Criterion (ii): The conically roofed form of Gonbad-e Qābus is significant as a prototype for the development of tomb towers in Iran, Anatolia and Central Asia, representing architectural cultural exchange between the Central Asian nomads and ancient Iranian civilisation. Criterion (iii): Gonbad-e Qābus is exceptional evidence of the power and quality of the Ziyarid civilisation which dominated a major part of the region during the 10th and 11th centuries. IntegrityThe property expresses its value as an exceptional geometric structure and icon in the small town of Gonbad-e Qābus, clearly visible from many directions.