Here’s another image of Old St Peter’s, part-way through the transformation into New St Peter’s. The main entrance, steps and square are all still present. From the Getty website:
Federico Zuccaro (Italian, about 1541 – 1609). 25.9 x 41.3 cm (10 3/16 x 16 1/4 in.)
Using red chalk in a highly detailed manner, Federico Zuccaro depicted Saint Peter’s Square in Rome as it appeared in 1603, with the Egyptian obelisk in place at the extreme left and the church dome complete. At the left, the archepiscopal palace adjoins the old facade of Saint Peter’s basilica. In the center, the three-story benediction loggia begun by Pope Pius II in 1462 adjoins the loggia painted by Raphael, lightly sketched at the extreme right. The bastion for the papal guard protects the front of the Vatican entrance, and statues of saints Peter and Paul from the 1400s adorn the foot of the staircase.
I’m rather impressed with the Getty site here. Who of us knew this even existed? (Click for larger image)