Roman emperors built their summer residences away from the Palatine Hill, the area where the city residences were built. Hadrian, who ruled Rome from 117 to 138, initiated a great architectural project on the outskirts of Rome, trying to bring together all that he had seen during his many travels. For this reason, he had the Villa Adriana built, one of the most beautiful and well-kept examples of an imperial palace.
For the site of his new residence, he chose a resort not far from the Urbe. He chose Tivoli because at that time it was already known as a holiday resort and had the advantage of being close to the Urbe. The total area of the villa extended over 300 hectares, equal to that of a real city.
It was divided into three nuclei: the eastern quarters, the central quarters and the upper quarters. These three areas were connected by special passages that also allowed control of who entered and left. The complex was also surrounded by high defensive walls. The emperor's residence was located in the central part and was accessed through a monumental entrance with three exedras. It was impossible to overlook the baths, which were the preferred place not only for treatment but also for business.
Among the buildings of the eastern quarter, the most prominent was the Greek Theater, behind which rose the Palestra complex. The most important part of this area was the Greek and Latin Library, which was accessed through a large terrace, behind which was the Hall of Philosophers, probably reserved for hearings, next to which was the Maritime Theater, identical in shape and size to the Pantheon. It had a portico with a water channel. In the middle there was a small island with a villa on it, which could be reached by two revolving wooden bridges.
Villa Adriana represents the most eloquent aspect of Roman architecture of the period. The richness and magnificence of its rooms and the monumentality that characterizes the building as a whole express the great power of the Emperor Hadrian.