regrouped around a defensible acropolis, or were abandoned in favour of such positions elsewhere." In the western Mediterranean, the only new cities known to be founded in Europe between the 5th and 8th centuries were the four or five Visigothic "victory cities". Reccopolis in the province of Guadalajara is one: the others were Victoriacum, founded by Leovigild, which may survive as the city of Vitoria, though a 12th-century (re)foundation for this city is given in contemporary sources; Lugo id est Luceo in the Asturias, referred to by Isidore of Seville, and Ologicus (perhaps Ologitis), founded using Basque labour in 621 by Suinthila as a fortification against the Basques, modern Olite. All of these cities were founded for military purposes and at least Reccopolis, Victoriacum, and Ologicus in celebration of victory. A possible fifth Visigothic foundation is Baiyara (perhaps modern Montoro), mentioned as founded by Reccared in the 15th-century geographical account, Kitab al-Rawd al-Mitar. The arrival of a highly urbanized Islamic culture in the decade following 711 ensured the survival of cities in the Hispaniae into the Middle Ages. Beyond the Mediterranean world, the cities of Gaul withdrew within a constricted line of defense around a citadel. Former imperial capitals such as Cologne and Trier lived on in diminished form as administrative centres of the Franks. In Britain, where the break with Late Antiquity comes earliest in the 5th and the 6th century, most towns and cities had been in rapid decline during the 4th century during a time of prosperity until the last decades of the century, well before the withdrawal of Roman governors and garrisons; historians emphasizing urban continuities with the Anglo-Saxon period depend largely on the post-Roman survival of Roman toponymy. Aside from a mere handful of its continuously inhabited sites, like York and London and possibly Canterbury, however, the rapidity and thoroughness with which its urban life collapsed with the dissolution of centralized bureaucracy calls into question the extent to which Roman Britain had ever become authentically urbanized: "in Roman Britain towns appeared a shade exotic," observes H. R. Loyn, "owing their reason for being more to the military and administrative needs of Rome than to any economic virtue". The other institutional power centre, the Roman villa, did not survive in Britain either. Gildas lamented the destruction of the twenty-eight cities of Britain; though not all in his list can be identified with known Roman sites, Loyn