Crowds are gathering in St. Peter's Square for Pope Benedict XVI's first Sunday window blessing since his retirement announcement, and the second-to-last before he leaves the papacy.

Pope Benedict XVI attends a meeting with parish priests of Rome's diocese at the Paul VI Hall (Franco Origlia/Getty Images)

The traditional Sunday appointment normally attracts a few thousand pilgrims and tourists, but city officials expect that this historic occasion may draw up to 150,000 people.

The city threw on extra buses and subway trains, and is offering free shuttle vans for the elderly and disabled. Free hot tea is also being prepared to ward off the early morning chill.

Benedict shocked the world last week by announcing he is resigning on Feb. 28 — the first papal abdication in 600 years. He will live essentially a cloistered life in a monastery behind Vatican City's walls

(Copyright 2012 The Associated Press. All Rights Reserved)