What I life Roman emperors had can be witnessed at Hadrians Villa in Tivoli. An one of a kind archaeological complex close to Rome.
Back in the days, in the second century, emperor Hadrian had enough of the busy life in the big city. He was longing for a summer retreat close by in Tibur. He built a palace with his own plans and later ruled his empire from here. The traces of 30 buildings on 1 square kilometer are still seen today, which is a sheer wonder, hence two millennial have passed. Even more so, because his successors and other fellows ripped the marble and stones off the Villa and used it for other buildings.
The style of the Villa was quit innovative, combining Egyptian and Greek knowledge. One striking asset on site are the numerous tunnels, which functioned as servant-streets beneath the houses. You can stroll in them and get lost. Like on the whole compound. I would recommend taking your time, when you go there, to take large walks and to suck in the experience and to dream of ruling the world or so ;)
It is beautiful there and makes a great day-trip, if you stay in Roma, you can take buses or a rental car to go to Tivoli. And you better be quick: In 2006 the Villa Adriana was put on the list of the 100 most endangered sites of the World Monument Watch, hence it is vanishing day by day. Despite the fact, that it is an UNESCO World Heritage I had the feeling that tourists are not coming in masses, so it is much more pleasant than the sites in Roma.