<P> In 217, the Colosseum was badly damaged by a major fire (caused by lightning, according to Dio Cassius) which destroyed the wooden upper levels of the amphitheatre's interior . It was not fully repaired until about 240 and underwent further repairs in 250 or 252 and again in 320 . Gladiatorial fights are last mentioned around 435 . An inscription records the restoration of various parts of the Colosseum under Theodosius II and Valentinian III (reigned 425--455), possibly to repair damage caused by a major earthquake in 443; more work followed in 484 and 508 . The arena continued to be used for contests well into the 6th century . Animal hunts continued until at least 523, when Anicius Maximus celebrated his consulship with some venationes, criticised by King Theodoric the Great for their high cost . </P> <P> The Colosseum underwent several radical changes of use during the medieval period . By the late 6th century a small chapel had been built into the structure of the amphitheater, though this apparently did not confer any particular religious significance on the building as a whole . The arena was converted into a cemetery . The numerous vaulted spaces in the arcades under the seating were converted into housing and workshops, and are recorded as still being rented out as late as the 12th century . Around 1200 the Frangipani family took over the Colosseum and fortified it, apparently using it as a castle . </P> <P> Severe damage was inflicted on the Colosseum by the great earthquake in 1349, causing the outer south side, lying on a less stable alluvial terrain, to collapse . Much of the tumbled stone was reused to build palaces, churches, hospitals and other buildings elsewhere in Rome . A religious order moved into the northern third of the Colosseum in the mid-14th century and continued to inhabit it until as late as the early 19th century . The interior of the amphitheater was extensively stripped of stone, which was reused elsewhere, or (in the case of the marble façade) was burned to make quicklime . The bronze clamps which held the stonework together were pried or hacked out of the walls, leaving numerous pockmarks which still scar the building today . </P> <P> During the 16th and 17th century, Church officials sought a productive role for the Colosseum . Pope Sixtus V (1585--1590) planned to turn the building into a wool factory to provide employment for Rome's prostitutes, though this proposal fell through with his premature death . In 1671 Cardinal Altieri authorized its use for bullfights; a public outcry caused the idea to be hastily abandoned . </P>

When was the earthquake that destroyed the colosseum