Because her functions overlap with those of Zeus and Poseidon, Athena was often worshiped in tandem with these deities. Poseidon and Athena shared space in the Ionic temple on the Akropolis and at Cape Sounion because of their common interest in the Athenian polis, though the myth of their contest for the land shows that the relationship was one of opposition as well as affinity. At Kolonos in Attica, Poseidon Hippios and Athena Hippia (of horses) had a shared altar in Pausanias’ time (1.30.4). Athena’s interest in horses stemmed not only from her identity as a war goddess, but also from her role as a teacher of crafts and skills. Pindar (Ol. 13.63-86) is the earliest written source for the story that Athena gave a golden bridle to Bellerophon, which he used to tame Pegasos. In return, he dedicated an altar to Athena Hippia in Korinth, where her worship was focused primarily on the taming and training of horses. Poseidon, on the other hand, was the creator of the horse and the source of its fierce energy and speed.37
Athena’s mythic intimacy with her father Zeus is reflected in many dual cults, particularly those that deal with civic administration, law and justice. In Sparta they shared the titles of Agoraios (of the Marketplace), Xenios (of Strangers), and Amboulios (of Counsel), among others. In Athens, as we learn from the orator Antiphon (6.45), the Council-chamber or bouleuterion contained a shrine of Zeus Boulaios and Athena Boulaia (of Counsel), at which members prayed as they entered. Polieus, Zeus’ title as the protector of the city, is the masculine form of Athena’s common epithet Polias, while Zeus Phratrios and Athena Phratria shared altars throughout Attica as the patrons of the Athenian kinship groups known as phratries. Athena frequently accompanies Zeus when he appears in his chthonic guise as a serpent. In the fifth century, for example, a sanctuary of Zeus Meilichios and Athena existed at Athens. The same configuration of goddess and serpent companion is to be found in the cult of Athena Itonia (above) and of course in the presence of Athena’s serpent familiar, sometimes identified with Erichthonios, on the Athenian Akropolis.