Hadrian was declared emperor in AD 117 after the death of Trajan, who had been his mentor. He was forty years old when he ascended the throne. Originally from Spain as Trajan had been, the new immediately decided to resolve those military problems left open by his predecessor. Hadrian's strategy was different from that of Trajan in that he chose to contain and defend the existing boundaries of the empire instead of concentrating on great projects of battle.
Cultured and intellectual, Hadrian distinguished himself for the care he took in creating a good, efficient bureaucratic organization of the State.
The revision and simplification of the laws and bureaucratic mechanisms allowed him to dedicate his time to many side activities. Four years after his coronation, he began to inspect personally the provinces of the empire taking long trips which lasted years.
He was a man of peace and an acute observer of situations. Where necessary, he led the garrisons into victorious battles and studied all the necessary logistics with experts. He built bridges and roads in Gaul, reorganized the garrisons in Germany and constructed a great defensive valley in Brittany.
In Egypt, he constructed Antinopolis, a city on the Nile connected by ancient caravan routes to the Red Sea markets. Legend has it that Hadrian's favourite companion the young and handsome Antinoü died here, and thus the emperor dedicated the city to his memory.
Among the great construction projects in Rome for which Hadrian is responsible are the rebuilding of the Pantheon after its destruction by fire, the beginning of the Temple of Venus and Rome, and most of all, the construction of the villa near Tivoli, a masterpiece for its architectural riches and imagination.
In this splendid residence which was developed around an already existing building, the emperor spent the last years of his rule, dedicating his time to meetings with philosophers and intellectuals, entertaining them hospitably and discussing various topics with them.
While still living, Hadrian wanted to oversee the construction of his own tomb (the great mausoleum which today is Castel Sant'Angelo), and had it placed on the right bank of the Tiber with a bridge (Ponte Elio) constructed just to reach it.
Hadrian died in AD138 at the age of 62, and nominated as his successor Antonino, leaving him a consolidated and prestigious empire.