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:
Louisenlund is a site with one of Denmark's largest collection of megaliths. Some 50 stones standing upright among the trees, many of them over 2.5 metres high. The megaliths, which bear no inscription, stand on low mounds or over graves where the remains of burnt bones are buried. In the early Bronze Age and late Iron Age (1100 BC), it appears to have been common practice to set megaliths over graves of this kind. The stones stand alone or in small groups. As the site has not been archeologically investigated, it is not known why the stones were raised there. Another important megalithic site on Bornholm is Gryet, a small wooded area 5 kilometres west of Nexø. Originally it had more than 60 megaliths. Some have now been removed while half those remaining have fallen to the ground. The highest of them, once standing on the mound towards the south of the wood, was removed in the 17th century to be used as a gravestone. Louisenlund was bought by King Frederik VII when he visited Bornholm in 1851. He named it after his mistress, Countess Louise Danner.