The art of fortification had reached a high state of development even at the dawn of Indus Civilization in India. There were naturally variation of form in several centuries consequent on difference of concept. As a result of pressing circumstances and religious injunctions every ruler regarded it his sacred duty to construct a fort. As a result of this zeal the land was studded with fortified structures. This book traces the development of the art of fortification right from the period of Indus Civilization up to the period of emperor Harshavardhana. Some illustrations.