In the early hours of 20 August 1989, the pleasure boat 'Marchioness' sank in the River Thames close to Southwark Cathedral.
The Bishop of Southwark will preside at this service.
There will be a chance to hear from survivors and the families of the 51 people who died that night.
At the end of the Eucharist, flowers can be laid at the memorial to the disaster at the west end of Southwark Cathedral. Listing the names of those who died, the memorial was unveiled by Diana, Princess of Wales.
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