in antiquity, a field or vacant plain in a city, not built upon, left vacant on account of shows, combats, exercises, or other uses of the citizens.

**Campus Maii**, in ancient customs, an anniversary assembly of our ancestors held on May-day, when they confederated together for the defence of the kingdom against all its enemies.

**Campus Martius**, a large plain in the suburbs of ancient Rome, lying between the Quirinal and Capitoline mounts and the Tiber, thus called because consecrated to the god Mars, and let apart for military sports and exercises to which the Roman youth were trained, as the use and handling of arms, and all manner of feats of activity. Here were the races run, either with chariots or single horses; here also stood the villa publica, or palace for the reception of ambassadors, who were not permitted to enter the city. Many of the public comitia were held in the same field, part of which was for that purpose cantoned out. The place was also nobly decorated with statues, arches, columns, porticoes, and the like structures.

**Campus Scleratus**, a place without the walls of ancient Rome, where the Vejals who had violated their vows of virginity were buried alive.