The presiding magistrate at the pompa circensis[1] rode in a two-horse chariot; behind him are the young nobiles who led the parade on horseback (4th-century opus sectile from the Basilica of Junius Bassus)
^As identified by Katherine M. D. Dunbabin, "The Victorious Charioteer on Mosaics and Related Monuments," American Journal of Archaeology 86.1 (1982), p. 71.