The Ludus Magnus is the largest of the gladiatorial arenas in Rome. It was built by the emperor Domitian (81-96 AD) in the valley between the Esquiline and the Caelian hills. The still visible ruins of the monument belong to a second building stage attributed to the emperor Trajan (98-117).
The Ludus Magnus was located in this area as it was built for the performances to be held at the Colosseum. To facilitate connections between these two buildings, an underground gallery linked the two buildings. The path, with an entrance 2.17 m wide, began underneath the amphitheatre and reached the Ludus at its southwestern corner.
At the centre of the Ludus Magnus, built on two levels, there was an ellipsoidal arena in which the gladiators practiced. It was circumscribed by the steps of a small cavea, probably reserved for a limited number of spectators. The cavea had a four-sided portico (of about 100m per side) with travertine columns. It led to a number of outside rooms, to be used by the gladiators and as services for the performances. Only a few ruins in Travertine remain of the colonnade which was raised in the place where the columns were probably located originally.
In the northwest corner of the portico, one of the four small, triangular fountains has been restored. It lies in the spaces between the curved wall of the cavea and the colonnade. A cement block remained between two brick walls, converging at an acute angle.
The entrances to the Ludus Magnus were built on the main axes. The one at via Labicana, at the center of the building's northern side, was probably reserved for important people, since a decorated place of honour was found on the cavea.
Ludus Magnus gradually fell out of use, along with the Flavian amphitheatre, when gladiatorial combat was outlawed in the 5th century. The building was abandoned in the sixth century when it housed a small cemetery. By the middle of the sixth century, the area was no longer cared for and numerous churches were built, as the population continued to decrease.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.