The service at Lihou headland will remember those who died in the MV Prosperity disaster in the mid 70s.
The Guernsey Association of Royal Navy, Royal Marines & Merchant Navy will hold a memorial service today (5 September) to remember the seamen who died when their cargo ship foundered in a storm.
It is being held on national Merchant Navy Day which honours the sacrifices of Britain's merchant seamen.
The MV Prosperity was a Greek freighter with a cargo of timber that lost engine power off Perelle in a furious storm in January 1974.
It came aground on the Conchee Reef but rescue efforts were hampered by the weather and the cargo of wood that made approaching the ship difficult.
All 18 crew died after abandoning ship and 16 are buried at Le Foulon cemetery.
The service at the Prosperity Memorial at Lihou Headland is open to all and begins at 10.30.

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