The Arch of Augustus at Aosta was dedicated to the Emperor Augustus by the Roman Senate in 27 BC and is the oldest Roman arch which survives. It signaled the end of the via Flaminia, which connected the cities of Romagna to Rome, and spans the modern Corso d'Augusto (the ancient decumanus maximus), which led to the beginning of another road, the via Emilia, which ran northwest to Piacenza.

Its style is simple but solemn. The central arch, which is of exceptional size, is flanked by two engaged columns with fluted shafts and Corinthian capitals. The four clipei (shields) placed next to the capitals each depict Roman divinities: Jupiter and Apollo on the Roman side, Neptune and Roma facing the city of Rimini.

The gate's principal function, aside from functioning as a city gate, was to support the lavish bronze statue of Augustus, depicted driving a quadriga (a chariot drawn by four horses abreast).

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