VATICAN CITY - Benedict XVI has left Vatican City for the final time as pope.

The retiring pontiff was flown by helicopter to a papal retreat in Castel Gandolfo, where he was greeted by well-wishers.

Benedict individually greeted cardinals in Rome's Sala Clementina Hall this morning during his final hours of papacy. He had presided over his final general audience Wednesday before tens of thousands of cheering crowds in Saint Peter's Square. He thanked everyone for respecting his decision to step down, saying earlier this month that at 85 years old, he didn't have the strength of mind or body to carry on.

Benedict, who became pope in 2005, is the first pontiff in 600 years to step down. Vatican officials say he will be known as 'Emeritus Pope,' or 'Your Holiness.'