The Arch of Drusus (Arco di Druso) is often thought to be a triumphal arch, but in reality it is no more than a part of the Antoninian aqueduct supplying water to the Terme di Caracalla.
Arch of Drusus Rome
The arch was constructed in the 3rd century and is located almost immediatetely behind the Porta San Sebastiano, at the time called the Porta Appia.
In those days it was also the entrance to the safety courtyard of the Porta Appia, a courtyard where the Municipal Tax Office was situated as well.
The Arch of Drusus was brought to light during excavations in 1931.
The monumental impression it makes is mostly caused by its location along the important Appian Way.