St Francis' Monastery & Church Pula

Built in 1285, Pula's Franciscan monastery has an extraordinary 15th-century gilded altarpiece behind the altar of its cavernous church – but that's not its only, or even its oldest, treasure. Set into the floor of a Gothic chamber accessed via the Romanesque cloister is a Roman mosaic featuring a hippocampus (fish-tailed horse) and a swastika.