The clergy and congregations of Southwark Cathedral and the church of St Magnus the Martyr, whose parish boundaries meet on London Bridge, process to the centre for a short service.
This Thames tradition follows the Orthodox custom of hurling a cross into water as a symbol of Christ's baptism which is celebrated on the Sunday after the Epiphany.
The annual London Bridge event, which draws on ancient customs, was established seven years ago at the initiative of Fr Philip Warner, parish priest at St Magnus.
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