I received this nice card from a swap earlier this year. It's only my second postcard mailed from the Vatican City.
St. Peter's Square (Piazza San Pietro in Italian) is located directly in front of St. Peter's Basilica in Vatican City, the papal enclave within Rome (the Piazza borders to the East the rione of Borgo).
The open space which lies before the basilica was redesigned by Gian Lorenzo Bernini from 1656 to 1667, under the direction of Pope Alexander VII. Bernini had been working on the interior of St. Peter's for decades; now he gave order to the space with his renowned colonnades, using the Tuscan form of Doric, the simplest order in the classical vocabulary, not to compete with the palace-like façade by Carlo Maderno, but he employed it on an unprecedented colossal scale to suit the space and evoke emotions awe.
St. Peter's Square today can be reached from the Ponte Sant'Angelo along the grand approach of the Via della Conciliazione (in honor of the Lateran Treaty of 1929). The spina which once occupied this grand avenue leading to the square was demolished ceremonially by Benito Mussolini himself on October 23, 1936 and was completely demolished by October 8, 1937. St. Peter's Basilica was now freely visible from the Castel Sant Angelo. The effect of its demolition, however, was to destroy the characteristic Baroque surprise. The Via della Conciliazione was completed in time for the Great Jubilee of 1950.
The stamp is an Easter stamp issued earlier this year.