Kate Middleton andPrince Williamare learning about the past, present and future of Boston’s waterfront.

The Prince and Princess of Wales, both 40, continued their visit to the U.S. on Thursday afternoon with an outing in Boston Harbor. After learning how Boston has successfully driven climate innovation earlier in the day at Greentown Labs, they saw the changing face of the city’s shoreline as it contends with rising sea levels.

The couple wrapped up warm in scarves and long wool coats for the outdoor visit in the 32-degree weather, which felt even colder along the water.

Prince William and Kate Middleton.Chris Jackson/Getty

William, Prince of Wales and Catherine, Princess of Wales visit east Boston to see the changing face of Boston’s shoreline as the city contends with rising sea levels on December 01, 2022 in Boston, Massachusetts.

Kathy Abbott, CEO of Boston Harbor Now said it was so cold on the outing that she offered William her hand warmer, but the prince replied, “No, thank you.”

“I don’t want to be rude, I’m keeping them [hands] in my pockets, when I can feel them again it will be better,” William said.

Prince William, Prince of Wales and Catherine, Princess of Wales visit east Boston to see the changing face of Boston’s shoreline as the city contends with rising sea levels on December 01, 2022 in Boston, Massachusetts.

They also spoke with Carole Charnow of the Boston Children’s Museum, who told them about plans to protect the museum.

She told William: “Hopefully the children will be playing in the waters next time you come here.” The prince replied: “Hopefully not in temperatures like this!”

Prince William, Kate Middleton, Mayor Michelle Wu and Reverend Mariama White-Hammond.Chris Jackson/Getty

Prince William, Prince of Wales and Catherine, Princess of Wales speak with Mayor Michelle Wu and Reverend Mariama White-Hammond as they visit east Boston to see the changing face of Boston’s shoreline as the city contends with rising sea levels on December 01, 2022 in Boston, Massachusetts.

After the outing, PEOPLE spoke with Mayor Wu about the Prince and Princess of Wales' visit and how they’ve interacted with Bostonians.

Kate Middleton.Chris Jackson/Getty

Catherine, Princess of Wales visits east Boston to see the changing face of Boston’s shoreline as the city contends with rising sea levels on December 01, 2022 in Boston, Massachusetts.

Living Seawalls designs panels designed to mimic natural habitat formations like rock pools and mangrove roots that can be fitted to waterfront infrastructure to promote marine biodiversity. Over the coming months, Living Seawalls will work with the Stone Living Lab to design, manufacture and install these panels in two sites along Boston Harbor.

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Kate andPrince William’s three-day visit to the U.S. — their first sincespending time in New York City back in 2014— will lead to Friday evening’sEarthshot PrizeAwards ceremony. There, five winners from the pool of finalists will be announced. They will each receive $1 million in grants to scale and accelerate their project’s goals, plus support from the Earthshot network.

Prince William, Prince of Wales and Catherine, Princess of Wales visit east Boston to see the changing face of Boston’s shoreline as the city contends with rising sea levels on December 01, 2022 in Boston, Massachusetts.

A sourcetells PEOPLE, “The prize has become the Prince’s Super Bowl moment of the year, and he looks forward to continuing to use the platform each year to shine a light on some of the most impactful projects doing amazing things around the world to save our planet’s future.”

Kate andPrince Williamkicked off their visit to Boston on Wednesday with a welcome at Boston City Hall from Mayor Michelle Wu. That night, they headed to the TD Garden to watch the Boston Celtics take on the Miami Heat, sitting courtside for the basketball game.

source: people.com