To the north of the Altis and west of the Stadium were the Treasuries, housing votives and offerings of various Greek cities and colonies. The oldest and largest treasury, and the farthest east, is the Gela treasury, dating to circa 600 BC. West are the Treasuries of Megara, Metapontum, and Selinus. Next is an unknown structure, perhaps an altar to Gaia. Further west are the badly ruined Cyrene, Sybaris, and Byzantium treasuries; then the Epidamnos, Syracuse, and Sikyon treasuries. The Sikyon treasury is well preserved and dates to circa 480 BC. Beyond is an altar to Herakles.

South of the treasuries against the retaining wall are the statue bases of the Zanes, sixteen bronze statues of Zeus, built as a warning with money collected in fines from Olympic cheaters.

Treasuries Nearest Heraion Treasuries from the West
Treasury of Sikyon Treasuries viewed from Stadium