The foundations for the temple of Ares are dated to an earlier period than that of the superstructure (dated to the 5th century BC. ), now located a short distance from the western end of the temple of Hephaestus. From those fragments, archaeologists have determined they belonged to a Doric peripteral temple of a similar size, plan and date to the Temple of Hephaestus. Marks on the remaining stones indicate the temple may have originally stood elsewhere and then dismantled, moved, and reconstructed on the Roman base - a practice common during the Roman occupation of Greece.
Recent excavations in Pallene, to the east of Athens, have uncovered what are believed to be the original foundations of this temple. If this identification is correct, it also shows that the temple was originally dedicated to Athena.
Based on what little archaelogical evidence still remains, the temple stylobate is estimated to be 16.76 X 36. 25 m., slightly larger than the "Theseum," which measured 15.18 x 33.241 m. at the bottom step.
Camp II, John McK. "The Athenian Agora: A Short Guide to the Excavations." The American School of Classical Studies at Athens, (2003)
Ross, "Das Theseion tnd der Tempel des Ares," (1892)
Shear, Hesperia V, (1936:6-14); Hesperia VI(1937:pl IX)