Prince William and Princess Kate are heading across the Atlantic for a three-day visit to Boston in celebration of the Earthshot Prize Awards.
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The royal couple will begin their tour on Wednesday – with an incredibly powerful tribute set to greet them.
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William and Kate – who are on their first official overseas trip under King Charles's reign – will attend a welcome event outside Boston City Hall, attended by Michelle Wu, the city's major.
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They will then formally begin the countdown to Earthshot by lighting up City Hall – and other prominent buildings in Boston – green, in a spectacular visual tribute.
Boston's landmarks will be lit up green by the Prince and Princess of Wales
William and Kate's visit will culminate in the star-studded Earthshot Awards on Friday night. Superstar singer Billie Eilish will lead a stellar line-up for the awards ceremony, founded by William to recognise and scale-up environmental solutions to repair the planet.
Other acts to feature at the MGM Music Hall include Annie Lennox and Ellie Goulding.
David Attenborough is a strong supporter of the Earthshot Prize
Broadcaster Sir David Attenborough, a supporter of the Earthshot Prize since its inception, will voice the opening of the show while Oscar-winning actress and Earthshot judging panel member Cate Blanchett will narrate a look back at the 2021 winners.
The Earthshot Prize is now in its second year, and among the 15 finalists vying for £1 million awarded to each of the five category winners are a cleaner-burning stove initiative in Kenya and a bubble barrier made in the Netherlands to prevent plastics entering oceans.
There are also finalists from the UK for the first time, with two British-based entries being selected.
William and Kate arriving for the 2021 Earthshot ceremony
Notpla Hard Material – a start-up run by Pierre Paslier and Rodrigo Garcia Gonzalez in London – makes packaging from seaweed and plants as an alternative to single-use plastic, and has already produced more than one million biodegradable takeaway food boxes for the firm Just Eat.
The other UK finalist – Low Carbon Materials, based in County Durham – uses unrecyclable plastic waste to make traditional concrete blocks carbon-zero.