The Hephaestus Temple was started in 449 BC and completed in 416-415 BC. It was converted to a christian church and since it was used, it was preserved.
Looking at the Temple of Hephaestus and the Agora from the Acropolis
Michael in the Ancient Agora
The Museum of the Ancient Agora in the reconstructed Stoa Attalos. There is some controversy that the 1950's reconstruction did not have enough original historic fabric to be truly accurate. The statue below is believed to be Aphrodite.