Although hiding a Catholic church behind the columns this magnificent structure is but the tip of the iceberg of what lays underground (which you can also visit). The age and durability of this structure just made us say "wow".
Once you have seen above ground (where the columns are) don't miss going around the corner (at Via Portica, 2) to the Foro Romano, which is part of the Temple complex. During the Roman era, those columns you see were not street level: they were around 20 feet higher. The area you go underground to see was the street-level Forum...
The plaque read established 01BC, I believe. Regardless, it has been around since before Christ was born. It's amazing to see how well preserved it is. It's just beautiful to be so old. What an amazing thing to see.