Royal Marines beat the heat while practising Beating Retreat ahead of ceremonial display

The Massed Bands of the Royal Marines have been rehearsing at HMS Excellent in Portsmouth for a ceremonial event in London.

The 200-plus musicians are preparing for Beating Retreat at Horse Guards Parade.

"It only happens once every two years, and it's the only thing that we do that brings all the members of the Royal Marines Band Service together," said Lieutenant Colonel Huw Williams, principal director of music Royal Marines.

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A prestigious occasion

"It's a very special kind of prestigious ceremonial occasion. It's highlighting the Royal Navy in London, which, of course, you don't get the chance to do all that often."

The Royal Marines musicians carry out intricate routines – all while playing their instruments – and the current high temperatures make rehearsals even more intense.

"I didn't really think it would be this warm and so adapting to that is definitely a challenge," said Musician Emma Simms.

Despite the heat, it was the job of the renowned 40-strong Corps of Drums to set the tempo.

"We have directions that we're told to put down in our music, so that helps us to know where we're going," explained Musician Jack Cottle.

"But to be honest, the buglers and the drum majors do all that sort of work. A lot of the time we're just following the directions that are on our music."