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Altar of the Twelve Gods Near the middle of the open square, somewhat to the north, lay the Altar of the Twelve Gods (Fig. 7), today largely hidden under the Athens–Piraeus railway (1891). A corner of ... Altar of the Twelve Gods Near the middle of the open square, somewhat to the north, lay the Altar of the Twelve Gods (Fig. 7), today largely hidden under the Athens–Piraeus railway (1891). ... Figure 7. Altar of the Twelve Gods, originally dated 522/1 B.C., with later rebuildings. ... Physically, we are at the heart of the city. "Amongst those of the Peisistratids who held the annual magistracy at Athens was Peisistratos, son of Hippias the tyrant (named after his grandfather), who during his archonship set up the Altar of the Twelve Gods in the Agora and the Altar of Apollo in the shrine of Apollo Pythios.