Final answer:
The statue outside of the Flavian Amphitheater, or Colosseum, was originally a colossal statue of Nero, later repurposed as the sun god Sol. The equestrian statue of Marcus Aurelius, often associated with ancient Rome, is found at the Capitoline Hill, not the Colosseum. However, the life-size statue of Aulus Metellus is stored indoors at the Musei Capitolini.
Step-by-step explanation:
The statue that originally stood outside of the Flavian Amphitheater or Colosseum in Rome was not the statue of Aulus Metellus but rather a colossal statue of Emperor Nero, which was later remodeled into the sun god Sol. However, many visitors associate the statue of Marcus Aurelius, an equestrian statue located at the Capitoline Hill, with the center of Rome. While the life-size statue of Aulus Metellus is an important artifact, depicting a magistrate in oratorical pose, it was never located at the Colosseum but is significant in its own right.
In 1538, the equestrian statue of Marcus Aurelius was repositioned to the center of the Piazza del Campidoglio on the Capitoline Hill as a part of Michelangelo's design for the area and has since become a symbol of the city. While the original Marcus Aurelius statue has been moved indoors for conservation, visitors can see a replica of it at the same location. Similarly, the statue of Aulus Metellus, identified as such due to the inscription, has also been moved indoors to the Musei Capitolini where it can be visited today.
It should be noted that the original location of the equestrian statue of Marcus Aurelius is unknown, but its presence in central Rome has made it a prominent feature of the city's landscape for centuries. Furthermore, it's important to clarify that the Colosseum's reference comes from a different colossal statue, that of Nero, and not from the statue of Aulus Metellus or Marcus Aurelius.