Which divinity the temple was dedicated to is not exactly clear, whether it was Tibur, or Hercules, or Vesta or Alburnea, the Tiburtine Sibyl. The temple has been dated at around the middle of the 2nd C. A.D. What remains of it are the lower part of two of the façades Attic based columns (originally there were four), while along the side walls and at the end there are twelve fluted pseudo peripteral columns which abut against the cell wall.
The cells walls were decorated externally with semi-columns, of which only one diagonal ionic capitol remains which allows us establish the order.
In the Middle Ages the temple was changed into a church, dedicated to Saint George, and it was one of the most ancient deaconships, recorded as early as 978.