The Milan amphitheatre was built near the Porta Ticinese in the 2nd-3rd centuries AD when Mediolanum grew as economical and political importance while Rome declined. It remained in use until the city was one of the capitals of the Western Roman Empire (4th or 5th centuries). Later it was abandoned after Christianity imposed an end to arena games, but also as, in the wake of the imperial crisis, animals to be used in the amphitheatre were no longer imported. It became a quarry for construction stones as early as the 4th century AD, when the Basilica of San Lorenzo was built.
The edifice was demolished during a Barbarian attack on Milan, as it was located outside the walls and could therefore be used as stronghold by the attackers. The date of the event is uncertain, however: it could be 402, during the Visigothic invasion of Italy, or in 452, when northern Italy was ravaged by Attila, or during the Gothic Wars (6th century).
The scanty remains of the amphitheatre have, however, allowed the archaeologists to calculate that it was 129.5 metres long and 109.3 metres wide.References:
Redipuglia is the largest Italian Military Sacrarium. It rises up on the western front of the Monte Sei Busi, which, in the First World War was bitterly fought after because, although it was not very high, from its summit it allowed an ample range of access from the West to the first steps of the Karstic table area.
The monumental staircase on which the remains of one hundred thousand fallen soldiers are lined up and which has at its base the monolith of the Duke of Aosta, who was the commanding officer of the third Brigade, and gives an image of a military grouping in the field of a Great Unity with its Commanding Officer at the front. The mortal remains of 100,187 fallen soldiers lie here, 39,857 of them identified and 60,330 unknown.