Rome

Rome wears its age openly: a Republican temple props up a medieval bell tower, a Baroque church sits on an emperor's foundations, and traffic bends around a triumphal arch two thousand years old. This is a working capital of nearly three million people, not a museum, and Romans move through their ruins with easy indifference, parking Vespas against ancient walls and drinking espresso where senators once argued. The rhythm is unhurried and worth matching: lunch runs long, and the evening walk is a daily habit rather than an event. Some 2,500 cast-iron street fountains have poured drinking water since antiquity, so carry a bottle and fill it as you go.

Rome traces its founding to 753 BC and the legend of Romulus, though Etruscan kings ruled the early settlement on the Tiber's hills. A republic replaced the monarchy around 509 BC and expanded across the Mediterranean before Augustus turned it into an empire in 27 BC. At its height the city held perhaps a million people, fed by aqueducts and grain fleets. When imperial power moved east and the western empire dissolved in the fifth century, Rome shrank to a few thousand residents living among collapsing monuments, its Forum grazed by cattle. The papacy kept the name alive through the Middle Ages, and from the fifteenth century popes rebuilt the city in Renaissance and Baroque form, raising St Peter's and opening grand piazzas. In 1870 Rome became the capital of a newly unified Italy, and the twentieth century cut broad avenues through the old districts. Today it governs a modern nation while three millennia of building stand layered in the same streets. Via dei Fori Imperiali shows the method: a boulevard cut in the 1930s straight over the buried forums of the emperors, which are still down there under the paving.

Three days covers the ancient core, the Vatican and the fountain-linked centre. Five reach the Aventine, the Appian Way and the quarters south of the walls, where Rome stops performing and simply carries on.