In a church service in the middle of London Bridge, the River Thames will be blessed this weekend and the public is invited to attend.
Local church leaders will conduct the blessing, which will follow a procession after mass at the Cathedral.
Its purpose is to bless those who work and look after the river and those who enjoy it. Special blessings are also said for those who have died on or near the river.
This Sunday (January 14) a procession will lead the way from Southwark Cathedral on the south bank, meeting a similar one from St Magnus The Martyr on the north bank, in the middle of London Bridge.
The blessing itself takes place at 12.30 pm and is free to attend.
Although this particular ceremony has only taken place for the last twenty years or so, there is evidence of groups throughout history giving thanks to their river – as far back as the ancient Egyptians who believed their Nile was a gift from the gods.