Q&A: What is the story of Knock Marian shrine?

Mary is shown with St Joseph, St John the Evangelist, a lamb and a cross on a mosaic of the apparition at Knock Basilica

As the final plans are set in motion for Pope Francis' visit to Ireland, the people of Knock are bracing themselves for thousands of visitors.

Knock was once a small village in the rural west of Ireland.

But when villagers said they had saw an apparition on the gable wall of a Catholic church 140 years ago, all that changed.

In 1979, Pope John Paul II visited Knock.

Now, Pope Francis follows in his footsteps. He is due to arrive on Sunday 26 August.

What will Pope Francis do at Knock?

Pope Francis is due to arrive by plane at Knock at about 09:45 local time. He will spend about an hour there.

He will travel through the crowds in the pope mobile before going into the chapel to pray privately.

He will then say the Angelus outside the shrine with the crowds gathered for his visit.

A total of 45,000 people secured tickets for Pope Francis' visit to Knock.

The Pope will then return to Dublin to say Mass in Phoenix Park.

What is special about Knock?

The Marian Shrine of Knock is a well-known place of Catholic pilgrimage in County Mayo in the west of Ireland.

An estimated 1.5m pilgrims from across Ireland and across the world flock to the shrine every year to pray at the place where an apparition of Mary, the mother of Jesus Christ, is said to have appeared in August 1879.

The rosary procession at Knock

Following the apparition, miraculous cures were reported. The first was that of Delia Gordon, a 12-year-old girl who had been deaf and suffered horrific pain.

It is said that her parents took her to the shrine where she knelt before the place where the apparition was seen. Her mother picked a piece of cement from the gable wall, blessed it and put it on her daughter's ear. The pain went immediately and she was no longer deaf.

Since the apparition, pilgrims have come to Knock in search of healing, reconciliation and peace. Some of them are praying for a cure.

Pope Francis is to visit the shrine on Sunday 26 August and 45,000 people have secured tickets to see him there.

That morning, the bells of Knock Shrine will ring out to signal his arrival and the Pope will spend some time in silent prayer before addressing the crowds gathered outside and praying with them.

What happened at Knock?

The story begins on 21 August 1879, when 15 people from the village witnessed an apparition of Mary on the gable wall of the parish church.

They said she appeared with St Joseph, St John the Evangelist, a lamb and a cross. They watched in pouring rain for two hours, reciting the Rosary, a Marian prayer.

The story goes that the watchers were soaked in rain but the gable wall and the apparition remained dry.

The witnesses, aged between five and 74, gave their testimony to a Commission of Enquiry later in 1879. It found their words "trustworthy and satisfactory".

In 1936, a second Commission of Enquiry heard from the two surviving witnesses, Mary O'Connell and Patrick Byrne.

Mary O'Connell ended her sworn statement with the words: "I am clear about everything I have said and I make this statement knowing I am going before my God." She died later that year.

Who was the 'Builder of Knock'?

Monsignor James Horan, a native of County Mayo, is often called the Builder of Knock.

Songs have been written about Monsignor Horan and his "miracle" of an airport, which was built on top of a bog

He was a spiritual leader to his congregation from the 1960s, but was also wily and lobbied persistently to raise finances for the shrine.

He even persuaded the powers-that-be to build an international airport close by - on top of a bog - to serve not only the needs of pilgrims but also the population of the west of Ireland.

Songs have been written about the monsignor and his miracle of an airport, completed in 1985.

The monsignor also had a major role in preparing for John Paul II's visit to Knock in September 1979.

He died suddenly while on pilgrimage in Lourdes in 1986.

What do pilgrims hope to gain from Knock?

Knock is a traditional annual pilgrimage for thousands: visiting the shrine is a tradition passed down through generations of families.

People spend a day in prayer, taking part in the Stations of the Cross or joining in candlelit vigils at the site.

They carry away Blessed Holy Water to share with family and friends. Many say they find Knock a place of peace and that they derive great consolation from their visit.

What happened at the last Pope's visit?

Pope John Paul II's visit marked the centenary of the apparition at Knock.

About 450,000 people came to Knock to see Pope John Paul II mark the shrine's centenary in 1979

He said the shrine was "the goal of my journey to Ireland".

He said an outdoor Mass there on Sunday 30 September which was attended by an estimated 450,000 people.

He met the sick, made the chapel a basilica and lit a candle at the gable wall, the scene of the apparition, for the families for Ireland.

What else happens at Knock?

People also travel to Knock to find the right partner in life.

The Knock Marriage Bureau opened in 1968 with the aim of helping people meet suitable spouses.

It is a Catholic organisation based on Main Street and offers its services with the assurance of "strictest confidence".

It is now known as Knock Marriage Introductions.

It has been responsible for nearly 1,000 marriages down the years.