Private games were held, probably for emperors, at a personal Colosseum found inside a “gigantic imperial palace” near the present-day Fiumicino airport, which serves Rome. The London Times has pictures. Accounts say it’s lavishly built with luxury materials and seats 2,000.
Clearly, the forerunner of the modern home theater. Who needs plasma when you can screen the action in life-size 3-D?