Dinsmoor, W. B ... American School of Classical Studies at Athens ... The well-preserved Temple of Hephaistos, standing on a low hill to the west of the Athenian Agora, was one of the only monuments visible when American excavations began on the site in 1931. Known throughout ... 1941 ... Known throughout its early modern history as the “Theseum,” it is still the Agora’s most conspicuous landmark.