Church on the far- flung island of San Pietro served as Venice's cathedral from 1451 to 1807. The interiour of Basilica di San Pietro di Castello, Basilica of St Peter of Castello in Venice, (originally known as Olivolo) was among the first to be inhabited in Venice, and the original church here was the seat of a bishopric as early as 775. The present church is an almost-but-not-quite Palladio design. Venice