By Peter Gould BBC News Online

Pope John Paul II returns to his native Poland this weekend for what promises to be an occasion for great emotion.

For the 82-year-old pontiff, who has become increasingly frail in recent months, it will be a sentimental homecoming.

He is spending four days in and around Krakow, where he was archbishop before his surprise election as pope in 1978.

The Polish Pope

Born: Karol Wojtyla Date: 18 May 1920 Place: Wadowice Elected: Oct 1978 Visits to Poland: 1979, 1983, 1987, 1991 (twice), 1995, 1997, 1999

Given his health, the people of the city know it may well be their last opportunity to see him on Polish soil.

Two million people are expected to attend the open air mass on Sunday that will be the highlight of the trip.

In addition to visiting religious sites, the Pope has set aside time to go to the cemetery where his parents are buried.

Illness

Before he returns to Rome, a helicopter will fly him over his home town of Wadowice, and the Tatra mountains he climbed as a young man.

Wawel Cathedral is on the Pope's itinerary

During his lengthy papacy, the pope has completed nearly 100 overseas tours, visiting more than 600 cities around the world, and clocking up 700,000 miles (1.1 million kilometres).

But he has not neglected his own country, and has returned to Poland several times during his papacy.

On the last visit in 1999, a bout of flu meant that he was unable to appear at the open-air mass in Krakow, an event attended by a million people.

Aware no doubt of their disappointment, the Pope is going back, perhaps for the last time, to the city that means so much to him.

The reception that awaits him is likely to be one of the highlights of a remarkable papacy. Some 95% of Poland's population of 39 million are Catholic.

Revered

As a young man, Karol Wojtyla witnessed at first hand the Nazi occupation of Poland, and the persecution that followed.

Polish upbringing: The young Karol Wojtyla

In 1942, he secretly began the religious studies that led him to the priesthood.

He was ordained after the war, but then had to face the religious intolerance of the communist regime.

These were experiences that shaped his life and his beliefs.

Many historians argue that the election of a pope from Eastern Europe was a factor in the subsequent collapse of communism.

There is no doubt that John Paul II is revered in his homeland. In a recent poll, 86% said his visit would be an important event in their lives.

Alongside the rapturous reception that awaits him, high security will be in force throughout his visit, with 12,000 police officers on duty.

Gun threat

There was concern last week when it was reported that a death threat had been made in a discussion forum on a Polish website.

Longest papacies

Pius IX: 31 years (1846-1878) Leo XIII: 25 years (1878-1903) Pius VI: 24 years (1775-1799) John Paul II: 23 years (1978 - )

The writer of the message, which was quickly removed from the site, claimed he had a gun and ammunition, and was planning to kill the Pope.

The Vatican has played down the incident, but it is being investigated by a police team that deals with internet crime.

The health of the pontiff will be uppermost in the minds of many Poles. Local hospitals have been put on standby, in case he requires medical treatment.

Waiting for the Pope: Premier Leszek Miller

John Paul II suffers from Parkinson's disease and arthritis. He now has limited mobility, and his speech is slurred.

He also tires quickly, and aides sometimes have to finish his speeches.

The leader of the Polish church, Cardinal Jozef Glemp, has called on Catholics to pray for the health of the Pope and the success of the visit.

Among political and civic leaders, he will meet the Polish president, Aleksander Kwasniewski, and the prime minister, Leszek Miller.

In Poland, these are more than just the normal courtesies afforded a visiting head of state.

John Paul II has a special place in the history of his country, and in the hearts of its people.