Prince William and Kate, the Princess of Wales, in Boston on Wednesday at a “Welcome to Earthshot” event with governor-elect Maura Healey listening to Mayor Michelle Wu. (Image: Boston City TV)

Prince William and Kate Middleton, the Princess of Wales, are in town for the 2022 Earthshot awards in Boston, but their itinerary brings them to Somerville on Thursday and Cambridge on Friday.

The Thursday visit is to Greentown Labs, an incubator for around 200 climate-tech businesses near Union Square, and the city was eager Wednesday to warn residents of the traffic snarls to expect from the first U.S. visit by the couple since 2014. From approximately 9 a.m. to noon, Somerville Avenue between Dane and School streets will be closed to “accommodate security measures for the British royal visit,” the city said via robocalls and emails, affecting “both directions of travel, the sidewalks and parking,” which will be closed to the public. The 87 bus will be rerouted temporarily too.

The Friday visit to Cambridge will be only by Middleton. As Prince William heads to the John F. Kennedy Presidential Library and Museum in Boston, she plans to visit Harvard University’s Center on the Developing Child at 11:15 a.m., according to media reports.

No traffic impacts were announced in Cambridge.

The Earthshot awards, with their ceremony Friday, are the invention of Prince William. They are named in the spirit of the 1962 “moonshot” challenge set by President John F. Kennedy in the 1960s, according to the organization, and go to five people with “cutting-edge environmental solutions.”

Middleton shakes hands Friday with Cambridge Mayor Sumbul Siddiqui in The Atrium in Harvard Square. (Photo: Denise Jillson/HSBA)

The royals met Wednesday with Boston Mayor Michelle Wu. The offices of the mayors of Cambridge and Somerville were asked if they would be receiving similar honors, but neither office responded immediately. Siddiqui met with Middleton on Friday, where the Princess of Wales also spoke with Lawrence Bacow, president of Harvard University. Middleton is “incredibly elegant and composed,” said executive director of the Harvard Square Business Association.

The conversation was very casual, but the mayor made it a point to thank Middleton for her work on mental health and early childhood development, Siddiqui said Friday.

Middleton shakes hands Friday with Lawrence Bacow, president of Harvard University. Mayor Sumbul Siddiqui is at center. (Photo: Harvard University)

Thanks to the presence of Harvard and the Massachusetts Institute of Technology, there is more or less a steady stream of the famous coming to Cambridge. Even the list of students can be glamorous, with Harvard class lists including names from Ashley Judd and Natalie Portman to James Murdoch and Malia Obama.

There are also times the famous and newsworthy visit. When Joe Biden visited Harvard as vice president in 2014, Cambridge city councillor Craig Kelley called a hearing to account for the level of police presence he encountered that day – and learned there had been more than 20 such visits that year by dignitaries including foreign heads of state and national, military and religious leaders, some calling for security up to rooftop sniper teams.

“As an international city, [Cambridge] has a great deal of experience handling a wide range of visits, including past presidents, national and international politicians, celebrities and other well-known dignitaries,” said Jeremy Warnick, director of communications and media relations for Cambridge police, on Wednesday. “Nearly every dignitary visit requires a level of traffic support, while others may be more involved and require tactical support and pre-visit sweeps from our Explosive Ordnance Disposal Unit to ensure safety and minimize any potential disruptions.”

“Regardless of the circumstances, we do everything we can to make any event as safe as possible,” Warnick said; “Dignitary visits can require extensive resources, planning and coordination internally and externally with our local, state and federal partners to ensure the safety and security of all involved.”