The remains of Early Byzantine Heraklion, like those of earlier periods, are scarce. Structural and architectural elements were usually reused in later buildings. We can assume that the city was hit hard by the earthquake of 365 AD and that its coastal front was swept away by the subsequent tsunami, like other Cretan coastal cities. But life went on, as the coins from the second half of the 4th and 5th centuries show. Architectural sculptures in second use, such as Corinthian lyre capitals imported from the quarries of the Byzantine capital, prove that the city was active in the 5th and 6th centuries and that maritime trade had recovered.

Layers of Early Byzantine occupation are found at great depths beneath later deposits. In Koronaiou str., part of a long building, perhaps an Early Christian basilica, and other remains were found at a depth of 8 metres from the surface. Architectural sculptures had also been incorporated into building phases dating back to the Arab period. Ceramics, small artefacts and coins attest to the continuous occupation of the city until the Arab conquest. Numerous coins of the emperors Heraclius (610-641 AD), Constantius II (641-668 AD) and Leo III (717-741) testify to the city’s survival during a period marked by a significant decline in coin production. Painted pottery of Gortyn, locally produced lamps and imported bronze buckles of the 7th and 8th centuries complete the monetary evidence and paint a picture of a flourishing economic life in the city during the period of the Arab raids, contrary to the traditional perception of decline.