Architectural Evolution of Defence Structures due to High Seismic Activity: A focus on Ancient Silk-route Cities of Sirohi District, Rajasthan, India

Geophysical earthquakes cause due by geosynclines & fault formation. The case study is based on ancient, fortified cities and how they got destroyed repeatedly by natural catastrophes. Also how they adopt different architectural technologies to cope with the disaster. with particular reference to ancient towns of the Sirohi district. We tried-to-study, an unexpected increase in the number of building forts and temples, which falls between time-space from the late sixth to the late sixteenth century A.D, we found that the impact of the catastrophe on the cities due to invaders is shallow in comparison to natural catastrophes like earthquakes and floods. The decline of the trade was also due to the natural catastrophe as fallen ruins are observed, fallen large rocks; even large temple structures were seen in rivers. We used primary and secondary sources for records of earthquakes. The earthquakes are prevalent in this region, which is why we also mention indigenous folklore, literature, chronicle texts, and bard traditions of a pilgrimage. Our first finding was the site of Bandiyagarh, a massive fort on a steep hill that has fallen objects, i.e., huge fallen rocks, cracks, fallen fragments of temples, structural complexes etc. as observed, all this destruction is caused by natural calamities of the earthquakes. In the ancient city of Chandrawati and other linked cities, we found that the temples are designed to absorb the waves of the earthquakes because as observed the Adhisthana (basement) was raised with bricklayer and Jagati (platform) was built through stones.