St. Peter's Square (Piazza San Pietro) is the massive plaza located directly in front of St. Peter's Basilica. Designed by Gian Lorenzo Bernini between 1656 and 1667, the square is famous for its elliptical shape and its four-row-deep Doric colonnades. Bernini intended the colonnades to represent the 'motherly arms of the church' reaching out to embrace the faithful. At the center of the square stands an ancient Egyptian obelisk, which was brought to Rome by Emperor Caligula in 37 AD; it is the only obelisk in Rome that has not toppled since antiquity. The square is designed with two 'focal points' marked on the pavement; when standing on these spots, the four rows of columns perfectly align so that they appear to be just one single column, a testament to Bernini's mastery of perspective and geometry.