The construction of the Colosseum was very much a symbolic gesture to create a clear distinction between Vespasian and his predecessor, Nero.
The Vatican Museums is important historical artefacts and works of art in the world. Originally the site of the Vatican Museums was used for papal palaces.
The city's many piazzas (Piazza Navona, Piazza di Spagna (and the Spanish Steps), Piazza Venezia) and the city's fabulous fountains (the Trevi Fountain, the Fountain of the Four Rivers and others) are popular places for good reason. In addition to the masterpieces they contain, these areas usually are surrounded by good quality restaurants, fine shopping, and gelato shops (gelaterias) are usually easy to find.