The Rosary on the Coast event will see people assemble at more than 300 sites in England, Scotland and Wales.
The rallying call follows Poland holding a similar event called Rosary at the Borders last year where tens of thousands of Catholics gathered at locations along the country's 2,000-mile border to pray for the salvation of the country.
According to the Rosary on the Coast's website, Catholics in Poland "responded to what they sense as a movement of the Holy Spirit to gather around the coasts of their nations and pray to Jesus, the Divine Mercy, for a renewal of faith and respect for human life through the powerful intercession of Our Lady of the Rosary".
The Bishop of Clifton, Rt Rev Declan Lang, sent words of encouragement to participants of the event that will begin at 3pm.
Wiring on the Rosary on the Coast's website, he said: "I pray that through the example and prayers of Mary, the Holy Spirit may overshadow the Church in her mission to the world so that God's name may be glorified."
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