According to historian Cassius Dio, very special attractions were offered at the opening of the Colosseum, the largest arena of the ancient world, under Emperor Titus in 80 AD, including the spectacle of a naval battle and other performances on the water, such as a torch-lit water ballet. There are also many other reports of animal hunts and gladiatorial fights that drew audiences into the technically and functionally sophisticated amphitheater in Rome.
But how did the wild animals get into the arena? A research team from the Rome department of the DAI examined this question.
An innovation compared to the previous amphitheaters was the installation of two elevator systems in the basement, which allowed people, decorations, and animals to be brought into the arena. The trick was that the elevator system and its mechanisms were not visible to the spectators. Around the imperial box, where the senators also sat, there were 28 hidden hatches installed in the arena floor. When the hatches were closed, a cage loaded with an animal was pulled up under the arena floor with large winches. Then the 28 hatches were opened all together or one after the other so that the animals appeared in the arena as if by magic.
Cross-sectional model of the basement level of the arena with freight elevators, cavea, and ambulatories (Photo: H.J. Beste, DAI Rome) 
Digital model of the freight elevators (Modell: H.J. Beste, DAI Rome) 
Aerial view of the Colosseum from the southwest (Photo: H.J. Beste, DAI Rome)