Courtesy of the Andrew Dickson White Architectural Photograph Collection, ca. 1865-1950. The Division of Rare And Manuscript Collections, Cornell University Library

The monumental gateway to the Acropolis, the Propylaea, was designed by the architect Mnesicles in 437 B.C. The four Ionic columns at upper right form the western facade of the Temple of Athena Nike Apteros, which was completed in 426 B.C. The temple’s foundations had been exposed around 1840 (30 years before Stillman arrived on the Acropolis), when a Turkish gun bastion was removed from the site. The so-called Frankish Tower rising behind the temple was erected during the medieval period. In the 1870s, Heinrich Schliemann paid to have the building razed in an effort to remove all of the Acropolis’s post-classical buildings.