Normally in winter, the pope would give his weekly Wednesday general audience inside a hall within Vatican City, but the event was moved outside because of the anticipated huge crowds.
The pope didn't give the usual brief personal greetings to people afterward, but was to meet with delegations of heads of state in Vatican City.
Benedict, who stunned the world's Catholics when he announced his resignation just over two weeks ago, will leave office at 8 p.m. local time Thursday.
At that point, a transition period will begin, as around 115 cardinals gather in Rome to pick a successor in a secretive election known as a conclave.
The Vatican has been rewriting the rules to cope with an almost unprecedented situation -- Benedict is the first pope to resign in nearly 600 years.
He will meet with the cardinals Wednesday and Thursday, before being flown by helicopter to the papal summer residence at Castel Gandolfo.
There, from a balcony, he will greet crowds one last time before his resignation takes effect and the Swiss Guards, who by tradition protect the pope, ceremonially leave the residence's gate.
More details were given Tuesday of how the 85-year-old's life in retirement will play out.
He will keep the papal title Benedict XVI, rather than reverting to the name Joseph Ratzinger, and will be referred to as "his holiness," said the Rev. Federico Lombardi, a Vatican spokesman.
He will also go by the title his holiness "pontiff emeritus" or "pope emeritus."
Living out of the public eye in a small monastery within Vatican City, Benedict will wear a simple white robe, without the papal red cape, and will swap his red shoes for brown ones. He is expected to devote his time to prayer and study.
Catholic author Michael Walsh told CNN he was unsurprised by Benedict's desire for more privacy.
"He's a rather private man. He wants to get back to his books and his cats, he wants to get back to prayer," he said. "He's obviously coming towards the end of his life -- he's 85 -- so I understand that."
But, Walsh added, "what I don't understand is that he says he wants to be part of it all, which could be disastrous if you take it at face value," referring to Benedict's promise not to abandon the church.
"The notion that you have two people that claim to be pope, in a sense, is really going to be very confusing," Walsh said.
Vatican officials have said they don't anticipate any interference from Benedict as a new pope takes office.
However, his influence will be felt in as much as he appointed 67 of the cardinals who will enter the conclave.
Whoever his successor may be will have plenty on his plate, from allegations swirling in the Italian media that gay clergy may have made themselves vulnerable to blackmail by male prostitutes -- a claim forcefully denied by the Vatican -- to the festering issue of the church's handling of child abuse by priests.
Scandal flared again over the weekend, as Scotland's Roman Catholic archbishop was accused in a UK newspaper report of "inappropriate behavior" with priests. Cardinal Keith O'Brien, who contests the allegations, resigned Monday and said he would not attend the conclave.
The Most Rev. Philip Tartaglia, archbishop of Glasgow, will take his place until a new archbishop is appointed, the Vatican said Wednesday. "These are painful and distressing times," Tartaglia is quoted as saying.
The Vatican said Monday that a report by three cardinals into leaks of secret Vatican documents, ordered by Benedict last year and seen only by him, would be passed on to the new pontiff.
Meanwhile, the cardinals who must elect the new pope are already gathering in Rome, Lombardi said.