The Confessio (1615-17), which was designed by Carlo Maderno, is the sacred space in front of the main altar.
Two sets of steps lead down to the crypt, at the floor level of the old basilica. Here we find the Niche of the Pallia, which houses a silver casket. Newly woven pallia (woollen stoles) are placed here on the eve of the Feast of St Peter and St Paul, the patron saints of Rome. On the feast day itself (June 29th) the pope presents the pallia to all the Metropolitan archbishops who had been elected during the previous year.