Amphitheatrum Castrense
Having paid the almost obligatory visit to the Colosseum, most visitors to Rome never realize, and others are surprised to learn, that a second ancient amphitheater remains in the city. Indeed, at various times during the life of ancient Rome, even more amphitheaters existed. We know of at least one built of stone "" the amphitheater of Statilius Taurus "" and one of wood built by Nero: both stood among the sports and military training facilities in the Campus Martius complex. In fact, technically, there remain even now vestiges of yet a third amphitheater in Rome: a small training arena right next to the Colosseum, to the E, used by gladiators as they prepared for the real combat. It also seems reasonable to imagine that in so large a city as Rome, several further smaller structures of this type may have existed as well, not recorded in extant sources; and some of them may even have been of brick as well, since other brick amphitheatres are known, for example at Nola.
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