De architectura (On architecture, published as Ten Books on Architecture) is a treatise on architecture written by the Roman architect and military engineer Marcus Vitruvius Pollio and dedicated to his patron, the emperor Caesar Augustus, as a guide for building projects. As the only treatise on architecture to survive from antiquity, it has been regarded since the Renaissance as the first known book on architectural theory, as well as a major source on the canon of classical architecture.
It contains a variety of information on Greek and Roman buildings, as well as prescriptions for the planning and design of military camps, cities, and structures both large (aqueducts, buildings, baths, harbours) and small (machines, measuring devices, instruments). Since Vitruvius wrote early in the Roman architectural revolution that saw the full development of cross vaulting, domes, concrete, and other innovations associated with Imperial Roman architecture, his ten books give little information on these distinctive innovations of Roman building design and technology.