Featured Watercolor Building

Yes, but that building was built into the temple much later. It's very common for buildings to be recycled here. The Roman amphitheatre at Tarragona, for example has a sixth century basilica inside it.

 

The Medieval town of Arles was built inside the Roman arena, which served as a fortress.


The arena still had people living in it in the 19th century. But not anymore, arena in the centre, Roman amphitheatre on the right:

 

As usual, you all have taken it soooo much further! But this what I was attempting to say

 

I’d think those numbers 12 & 13 on the doors were probably made up by the artists.

 

I don't think so, I have never heard of an artist who added house numbers to their monument paintings. In fact they generally prefer their monuments without modern additions.
People lived in the remains of the temple, as you can tell from the later doors and windows. They needed their mail delivered, just like anyone else.
There was once a church in the Nerva Minerva temple complex as well.