Arch of Hadrian & Constantine

Hadrian's Arch (shown above) existed when the Emperor Constantine reigned. Constantine added to it as shown below:

The blue and green sections indicate parts added by Constantine's artisans to the then-existing Arch of Hadrian. The yellow sections show parts that were taken from other monuments and added to Hadrian's Arch to make "The Arch of Constantine."
One of the parts added by Constantine shows him with his troops:

The following frieze shows Constantine (his face seems to be missing) and his court:

Hadrian's Arch without the Constantine's additions would look something like this: