The Duchess of Cambridge's decision to join her husband at the launch of an ultra-marathon today was a surprise and her attendance was only revealed this morning.
The royal couple have lived on Anglesey for years and have always spoken of their love of the island.
William said a public goodbye a fortnight ago as he confirmed his young family would be leaving their Welsh home and moving "elsewhere" when his posting comes to an end this month, having completed his three-year tour as an RAF search and rescue helicopter pilot based at RAF Valley on Anglesey.
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A service to remember 'Operation Dynamo', the code name for the mass evacuation of allied troops in 1940, will take place on the beach.
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