This is carved into one of the marble stones in the temple's steps.
This is a Roman temple dedicated to the emperor Augustus and his wife Livi. It is located right in the heart of downtown Vienne, and has been part of the city's history since Augustus' reign. It was likely built between 20-10BCE, but was subsequently converted into a church in the XIth century. It underwent significant restorations in the XIXth century, but the rear part of the cella is still original, and it also appears as though the metopes, pediment, and corynthian columns are also original.
The most fascinating part of my visit to the temple was its condition. It is currently "closed" to visitors for restoration, however, the only evidence of this was a tiny sign, the mini-crane you see in my photos, and that tiny, pathetic fence. While I was there, people were freely entering the temple, children were playing on the front steps, and I was able to walk around and examine up-close the remnants of marble blocks that used to be part of the structure. As you can see below from my photos, anyone could have come one night with a van and taken an ancient carved piece of marble from a Roman temple! The French are so blasé about having these treasures in their cities.