The Piazza Navona is one of the most famous squares in Rome. It's located east of the river not far from the Vatican. This is where the Stadium of Domitian was located in ancient times and if you view the area from above, you can still imagine the circular form of the arena. The square itself is like a work of art, not only because of the sculptures and fountains but also due to the surrounding buildings. The ruins of the ancient arena are nearby and you can get a good idea of what the zone was like a thousand years ago.
Bernini's Fontana dei Quattro Fiumi is located at the center of the square along with the obelisk. The fountain represents the four great rivers of the world: the Rio de la Plata (the Americas), the Danube (Europe), the Nile (Africa), and the Ganges (Asia). It's one of the busiest squares in the city and is usually crowded with locals as well as street artists who come during spring and summer afternoons to paint and entertain the crowds of tourists. The Church of Sant'Agnese in Agone is another major landmark in the square. A popular Christmas market is held during the holiday season, but there is also a street market on weekends.