In 1970, during excavations at the Athens Agora, a wall was uncovered, belonging approximately to the middle of the 5th century AD. Built into this wall were fragments and vertebrae originating from the inner colonnade of the Parthenon. During excavations that took place in 1970 and 1972, 35 architectural members belonging to the Parthenon were discovered most of them built into the foundations of a 5th century BC arcade. The prevailing theory about the reason for the destruction is damages brought about by earthquakes witnessed at the end of the 4th century AD. The Parthenon seems to have been renovated in the rule of Heracleius praetor in Illyricum in the first decade of the 5th century AD.