The Basilica di San Lorenzo is one of the largest churches of Florence, Italy, situated at the centre of the main market district of the city, and it is the burial place of all the principal members of the Medici family from Cosimo il Vecchio to Cosimo III. It is one of several churches that claim to be the oldest in Florence, having been consecrated in 393 AD, at whi…The Basilica di San Lorenzo is one of the largest churches of Florence, Italy, situated at the centre of the main market district of the city, and it is the burial place of all the principal members of the Medici family from Cosimo il Vecchio to Cosimo III. It is one of several churches that claim to be the oldest in Florence, having been consecrated in 393 AD, at which time it stood outside the city walls. For three hundred years it was the city's cathedral, before the official seat of the bishop was transferred to Santa Reparata.