Who designed St. Peter's Square in Vatican City?

The well known St. Peter's Square in Vatican City was designed and built by Bernini between 1656 to 1667. Construction took place during the pontificate of Alexander VII (1655-1667). It is a great square that is made up of two different areas. The first has a trapezoid shape, marked off by two straight closed and convergent arms on each side of the church square. The second area is elliptical and is surrounded by the two hemicycles of a four-row colonnade. This was done because as Bernini said, “considering that Saint Peter’s is almost the matrix of all the churches, its portico had to give an open-armed, maternal welcome to all Catholics, confirming their faith; to heretics, reconciling them with the Church; and to the infidels, enlightening them about the true faith.”

Bernini had initially designed a three-armed portico, but after Alexander VII’s death, construction of the portico was halted. The third arm was never built. It would have enclosed the whole building and separated the ellipse from the “Borgo” quarter, thus creating a “surprise effect” for the pilgrim who suddenly found himself in the square. This effect was somewhat achieved by the buildings surrounding the square, the so-called “Spina di Borgo”, which naturally “closed in” the square.