the end of the period, the most precipitous drop coming with the breaking of the aqueducts during the Gothic War. A similar though less marked decline in urban population occurred later in Constantinople, which was gaining population until the outbreak of the Plague of Justinian in 541. In Europe there was also a general decline in urban populations. As a whole, the period of late antiquity was accompanied by an overall population decline in almost all Europe, and a reversion to more of a subsistence economy. Long-distance markets disappeared, and there was a reversion to a greater degree of local production and consumption, rather than webs of commerce and specialized production. Concurrently, the continuity of the Eastern Roman Empire at Constantinople meant that the turning-point for the Greek East came later, in the 7th century, as the Eastern Roman, or Byzantine Empire centered around the Balkans, North Africa (Egypt and Carthage), and Asia Minor. The degree and extent of discontinuity in the smaller cities of the Greek East is a moot subject among historians. The urban continuity of Constantinople is the outstanding example of the Mediterranean world; of the two great cities of lesser rank, Antioch was devastated by the Persian sack of 540, followed by the plague of Justinian (542 onwards) and completed by earthquake, while Alexandria survived its Islamic transformation, to suffer incremental decline in favour of Cairo in the medieval period. Justinian rebuilt his birthplace in Illyricum, as Justiniana Prima, more in a gesture of imperium than out of an urbanistic necessity; another "city", was reputed to have been founded, according to Procopius' panegyric on Justinian's buildings, precisely at the spot where the general Belisarius touched shore in North Africa: the miraculous spring that gushed forth to give them water and the rural population that straightway abandoned their ploughshares for civilised life within the new walls, lend a certain taste of unreality to the project. In mainland Greece, the inhabitants of Sparta, Argos and Corinth abandoned their cities for fortified sites in nearby high places; the fortified heights of Acrocorinth are typical of Byzantine urban sites in Greece. In Italy, populations that had clustered within reach of Roman roads began to withdraw from them, as potential avenues of intrusion, and to rebuild in typically constricted fashion round an isolated fortified promontory, or rocca; Cameron notes similar movement of populations in the Balkans, 'where inhabited centres contracted and