 With no more space available at that time, emperors began to be buried in other churches and monasteries around the city.The tombs located at the church of Holy Apostles are known only from lists in literary sources, one of which is contained in De Ceremoniis.Although the sarcophagi of the emperors were broken into by Crusaders during the Fourth Crusade in 1204, some of the oldest porphyry sarcophagi have survived