Supporting buildings
What did the underground passage connect to the Colosseum?
Colosseum
The Colosseum and its activities supported a substantial industry in the area. In addition to the amphitheatre itself, many other buildings nearby were linked to the games. Immediately to the east is the remains of the "Ludus Magnus", a training school for gladiators. This was connected to the Colosseum by an underground passage, to allow easy access for the gladiators. The "Ludus Magnus" had its own miniature training arena, which was itself a popular attraction for Roman spectators. Other training schools were in the same area, including the "Ludus Matutinus" (Morning School), where fighters of animals were trained, plus the Dacian and Gallic Schools. Also nearby were the "Armamentarium", comprising an armory to store weapons; the "Summum Choragium", where machinery was stored; the "Sanitarium", which had facilities to treat wounded gladiators; and the "Spoliarium", where bodies of dead gladiators were stripped of their armor and disposed of. Around the perimeter of the Colosseum, at a distance of 18 m (59 ft) from the perimeter, was a series of tall stone posts, with five remaining on the eastern side. Various explanations have been advanced for their presence; they may have been a religious boundary, or an outer boundary for ticket checks, or an anchor for the "velarium" or awning. Right next to the Colosseum is also the Arch of Constantine.