What architectural feature is NOT associated with the Colosseum?

The architectural feature that is not associated with the Colosseum is the flying buttresses. The Colosseum, a monumental amphitheater in Rome, utilizes a system of arches and vaults that distribute weight effectively, allowing for the large, open spaces characteristic of its design.

Flying buttresses are a hallmark of Gothic architecture, serving to support walls from the outside and allowing for taller structures with large stained glass windows. This design innovation emerged much later, around the 12th century, and is not found in Roman architecture, which preceded it.

In contrast, the Colosseum does incorporate other architectural elements such as Corinthian and Ionic columns, which are representative of the classic Roman style, as well as annular passageways that facilitate movement around the structure. These details contribute to the Colosseum's design and function, showcasing the architectural advancements of the ancient Romans without the use of flying buttresses.