Equirria

The Equirria (also as Ecurria, from *equicurria, "horse races") were two ancient Roman festivals of chariot racing, or perhaps horseback racing, held in honor of the god Mars, one February 27 and the other March 14.

The Equirria took place in the Campus Martius outside the sacred boundary of Rome (pomerium). The exact course is debated: perhaps near the Altar of Mars in the campus; or on the Tarentum, the site of the ludi tarentini, which became the Saecular Games; or the Trigarium. When the Tiber flooded, the Equirria were transferred to the Campus Martialis on the Caelian Hill, a field without permanent structures.

The Equirria were said to have been founded by Romulus, the son of Mars. Both appear on the oldest Roman calendars inscribed on stone. The Equirria are part of what Michael Lipka calls "temporal focalization" in the Roman conception of deity. The festivals of Mars—the February 27 Equirria, a feria on the Kalends of March (a day sacred also to his mother Juno), Agonalia March 17, Tubilustrium March 23, the ritual of the October Horse October 15, and Armilustrium October 19—cluster at his namesake month (Latin Martius), except for festivals of Mars in October to close the military campaigning season.

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