One of the PLA's longest serving employees, John Window, cuts the cake at Gravesend

Staff at the Port of London Authority have gathered along the river to mark the 100th anniversary of the PLA's creation.

Pilots, boat crews, vessel traffic services officers, divers, salvage teams and shore staff met at locations between Richmond and Gravesend to celebrate the authority's birthday.

Chief executive Richard Everitt told them: "Reaching 100 years is a major achievement.   It means 100 years of keeping the river open to traffic, 100 years of helping keep the river safe, 100 years of facilitating trade.

"That work is as essential today as it was 100 years ago.

"The need for our work will continue as long as people need to eat, wear clothes and have fuel for heating and power."

The gatherings at Richmond Lock and Weir, Bakers Hall in central London, the Thames Barrier Navigational Control Centre at Woolwich, and at London River House and Denton in Gravesend were the start of series of events to mark the centenary which include:

• A public exhibition at the Museum in Docklands - March 31
• A book about the history of the PLA - March 31
• A concert (Celebrating London and the Sea) in aid of the Royal National Lifeboat Institution - April 18
• The launch of the first of a series of five newly designed harbour patrol launches - June
• A parade of PLA boats during the Thames Festival - September

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