The peculiarities of the city of Rome, with its three-thousand years of practically uninterrupted occupation, creating perhaps the largest example of a stratified site in the world, force the traveller to move through monuments in a manner that is rarely chronological or typological. For this reason, the archaeological guide follows two different directions in presenting the city: the historical introduction, which explains its development with detailed references to the monuments in order of their appearance; and the guide itself, which provides an accurate description of the sites within the city, divided into four sectors. The goal is to use the monuments of Rome to recount its history and that of the famous and unknown people who inhabited it. The guide is thus designed as a tool for contemporary readers to orient themselves in ancient Rome, and acts as a compass, with points of reference (maps, reconstructions and chronological tables) that offer a continuous explanation of the traveller’s position in time and space at any given moment, whether the voyage is real or virtual. This helps the reader to make an ongoing comparison between the urban structure of ancient Rome and that of the modern city, between everyday, visible Rome and the invisible city of the ancients. Updated and detailed texts, spectacular colour images, numerous aerial views embracing the many archaeological areas, maps, and three-dimensional reconstructions help to unlock the secrets of what was once the “Capital of the World”.