Originally built as Theodoric's palace church and dedicated to the Saviour, it was rededicated to St Martin of Tours during the episcopate of Agnellus (556-569) and finally to St Apollinaris in the 9th century, probably after the saint's relics were translated there in 856. It is a standard western basilica with a nave and two aisles, an apse and arcaded colonnades. The sumptuous mosaics reflect the dominant role that mosaics had assumed in the churches of the Christian East; the architecture is subordinate. One of eight Ravenna sites on the UNESCO World Heritage List.