Queen Camilla was at the New York Public Library to promote reading. 

Dozens from the literary and publishing world gathered at the the library's Trustees Room. The queen was greeted by Anna Wintour. 

Sarah Jessica Parker and Dr. Anthony Marx of the New York Public Library toured a collection spanning 250 years of shared U.S./UK literary history, according to the British Embassy. 

They then commemorated "Winnie-the-Pooh," which is marking its 100th anniversary. 

After his visit to Harlem Grown, King Charles went to Rockefeller Center for a United Kingdom-United States trade event at Rockefeller Center. 

While King Charles was at Harlem Grown, Queen Camilla was at the New York Public Library at 42nd Street. She recently gifted them a new Roo doll to add to the library's collection. The stuffed animal is from the book "Winnie the Pooh," which is celebrating it's 100th anniversary. 

She met with actress Sarah Jessica Parker at the library. 

King Charles II met with young people and community leaders at Harlem Grown's 134th Street farm, the British Embassy said. Founded in 2011, Harlem Grown has a network of 14 urban farms across Harlem. 

The king toured the farm and planted lavender and mustard greens. He visited the farm's chicken coop. 

"This moment is bigger than Harlem Grown; it speaks to the shared values between communities across the globe. Whether in Harlem or the UK, investing in youth, food access, and green space creates stronger, healthier communities. This work is about growing people as much as it is about growing food. We are proud to represent that work here at home," Harlem Grown founder and CEO Tony Hillery said. 

"Harlem Grown didn't just change my life, it saved it, and that seed of hope it planted in a timid, mildly troubled girl grew into a now therapist, PhD student, and first-generation college graduate," Harlem Grown student ambassador Epiphany Adams said. 

"His Majesty's visit today reflects his longstanding personal commitment to sustainable communities and to the next generation of community leaders who will shape our future and further strengthen our relationship," British Ambassador Christian Turner said. 

It was another quick stop for King Charles as he visited Harlem Grown, a nonprofit organization in Harlem. His visit wrapped up just about an hour after he arrived. 

There were still additional items on the agenda of his visit, including an appearance at the Kings Trust gala later this evening. 

The royal visit comes at a turbulent time overseas as the war with Iran continues.

"At the moment, America has few international allies," said royal contributor Dr. Amanda Foreman. 

She explained the speech King Charles III made to Congress, stressing continuity "is huge and very important." 

In his address, the king stressed the importance of the alliance between the United States and the United Kingdom. 

Dr. Amanda Foreman, a royal contributor, said because King Charles doesn't own the Koh-i-Noor diamond he cannot give it away, even if he wanted to.

The nation owns the controversial diamond that came from India more than 150 years ago. 

"The king has no more power to return the diamond than he has to return Buckingham Palace to the people," Foreman said. 

The British Embassy said the royal couple met with around 90 guests at the National 9/11 Memorial and Museum, including family members of those killed in the attacks, and currently serving first responders. 

FDNY Commissioner Lillian Bonsignore, a 9/11 first responder herself, was on hand, the British Embassy said. 

"As New Yorkers and Americans, we are united in our pledge to never forget those we lost on 9/11. We will always remember the outpouring of support from so many people across the United Kingdom in the aftermath of the attacks and are grateful to King Charles III and Queen Camilla for returning to this sacred site," said former New York City Mayor Michael Bloomberg, who is chairman of the 9/11 Memorial & Museum. "As a new generation learns about the day that shook our city and the world 25 years ago, the 9/11 Memorial & Museum continues to be a place of reflection and inspiration." 

"We are honored to welcome Their Majesties to the 9/11 Memorial & Museum as the world remembers what took place on and after September 11, 2001," said Beth Hillman, President and CEO of the 9/11 Memorial & Museum. "Each year, we are privileged to welcome tens of thousands of visitors from the United Kingdom, many of whom are too young to remember that fateful day. Their Majesties' participation in this solemn ceremony ensures that the legacy of 9/11 will never be forgotten." 

Authorities said there are no credible threats against the king and queen during their visit to New York City.

That said, there's a massive security presence throughout the Big Apple, with visible police assets, large perimeters, and intermittent road closures. Expect traffic disruptions throughout the day. 

Photographers captured the moment New York City Mayor Zohran Mamdani greeted King Charles III. The king and queen had greeted New York Gov. Kathy Hochul and New Jersey Gov. Mikie Sherrill moments before. 

There's no word on what, if anything, Mamdani may have said to the royal couple, although prior to the event he said he might mention King Charles return the Koh-i-Noor diamond. 

The royals began their New York City trip at the 9/11 Memorial & Museum. They met with first responders and the families of victims.

The royals will then split up.

Queen Camilla will head to the New York City Public Library. She will gift a new Roo doll to the library's collections. The stuffed animal is a character from the book "Winnie-the-Pooh," which is celebrating its 100th anniversary of publication.

Meanwhile, King Charles will visit a nonprofit in Harlem. The community organization works with young people affected by food insecurity and opens green spaces for community members to enjoy. 

The two will also make a stop at Rockefeller Center before attending a reception for the King's Trust.

The king and queen spent several minutes talking with former New York City Mayor Michael Bloomberg before placing flowers at the waterfall pool at the National 9/11 Memorial & Museum. Bloomberg is the chairman of the museum. 

They then spent some time on a receiving line, where they were greeted by a number of New York City and Tri-State luminaries, including Govs. Kathy Hochul and Mikie Sherrill as well as New York City Mayor Zohran Mamdani. They also met with families of 9/11 first responders. 

Former FDNY Commissioner Thomas von Essen was on hand for the royal visit to the National 9/11 Memorial & Museum. He could be seen on a reception line as the royal couple made their way from the waterfall pools after laying flowers there. 

Former New York City Mayor Michael Bloomberg escorted King Charles III and Queen Camilla to the edge of the waterfall pools at the 9/11 Memorial & Museum. 

They spent several minutes talking before the king and queen laid some flowers at the memorial. 

King Charles III and Queen Camilla arrived in Washington D.C. on Monday afternoon.

They headed straight to the White House and met President Trump and first lady Melania Trump. The four had tea in the White House Green Room before touring the White House's latest beehive.

A formal ceremony welcomed the king and queen with a ceremonial military review.

King Charles and Mr. Trump held a bilateral meeting while the queen and first lady had their own meeting.

The king's trip marks his first to the United States since he assumed the throne in 2022, although he traveled to America 19 times before his coronation. 

His first official visit was in July 1970 with his sister, Princess Anne. He met with President Richard Nixon, was honored with a formal White House dinner and went to a baseball game with first daughter Tricia Nixon.

Another notable visit was in 1985. Prince Charles and Princess Diana met with President Ronald Reagan and first lady Nancy Reagan at the White House. 

In 2015, then-Prince Charles and Camilla, known at the time as the Duchess of Cornwall, came on a four-day official tour. The couple met with President Obama and then-Vice President Joe Biden at the White House. 

They also visited the National Archives, Arlington National Cemetery, George Washington's Mount Vernon estate in Virginia and stopped by Louisville, Kentucky. 

British monarchs haven't been the only members of the royal family to come to New York City. Princess Diana's sons, Prince William and Prince Harry, have been here several times. Here's a look at some of them chronologically:

Prince Harry made his first official visit to New York City in 2009, and went to, among other places, Ground Zero and a VA hospital in Manhattan. He also participated in a polo match on Governors Island to raise money for children orphaned by HIV/AIDS.

As part of their trip to the U.S. in 2014, Prince William and his wife, Catherine, now the Princess of Wales but then known as the Duchess of Cambridge, visited the 9/11 Memorial & Museum and attended a Brooklyn Nets game, where they met Jay-Z and Beyoncé, as well as NBA star LeBron James.

Princess Beatrice, the eldest daughter of Andrew Mountbatten-Windsor, formerly Prince Andrew the Duke of York, and Sarah Ferguson, attended the Met Gala in 2018.

Meghan Markle, the Duchess of Sussex and wife of Prince Harry, was on hand to cheer on Serena Williams, who was competing in the 2019 US Open women's final in Queens.

In 2021, Harry and Meghan attended Global Citizen Live from Central Park in support of vaccine equity amid the COVID-19 pandemic.

Two years later, Harry and Meghan's trip to New York City was marred by a harrowing paparazzi chase through the streets of Manhattan.

The high-profile visit comes on the heels of a man being charged with an attempted assassination of the president at the White House Correspondents Dinner and the war with Iran. 

The king will have his own protective detail from overseas. Local security will also be involved, according to a Secret Service spokesperson.  

"Residents, however, will see a large law enforcement presence throughout the city to secure the visit. There will be visible police assets, large perimeters around certain locations and intermittent road closures and traffic disruptions throughout the day," the spokesperson said.

New York City Mayor Zohran Mamdani will be joining King Charles and Queen Camilla along with Governors Kathy Hochul and Mikie Sherrill for a wreath-laying at the 9/11 Museum & Memorial Wednesday. 

Prior to that event, the mayor was asked if he would be meeting with the king privately, and if so, what message he might have for him. 

"I'll be saying that today I'll be attending a wreath laying alongside a number of other elected officials, including Governor Hochul, Governor Sherrill, and the focus of that wreath-laying is to honor the more than 3,000 New Yorkers who were killed in the horrific terror attacks of September 11th. And that's what I'm really looking to do at that event," Mamdani said. "You know, if I was to speak to the king separately from that, I would probably encourage him to return the Koh-i-Noor diamond."

The Koh-i-Noor diamond was given to Queen Victoria in 1849. It was given as part of the Treaty of Lahore that ended the first Anglo-Sikh War. 

The jewel is thought to have originated from India. Many Indians consider it a stolen piece of their national history, taken during the British empire.    

During their state visit to the U.S., King Charles III and Queen Camilla will attend an event at the 9/11 Memorial & Museum in New York City and take part in a wreath-laying ceremony on Wednesday morning.

Sixty-seven British citizens were among those killed in the terror attacks on Sept. 11, 2001.

The king is also expected to meet with families of victims in honor of the 25th anniversary of the attacks.

New York Mayor Zohran Mamdani is also scheduled to be at the event, but is not expected to meet privately with the king.

King Charles has been battling an unspecific form of cancer since February of 2024.

Buckingham Palace has been very tight-lipped about his health. There has been no official update on his treatment other than a pre-recorded video in December in which he said his "schedule of treatment" would be reduced in 2026.

The king has been proactive since being diagnosed, encouraging people to get early screenings and saying at one time, "Early diagnosis quite simply saves lives."  

"I know from my own experience that a cancer diagnosis can feel overwhelming. Yet, I also know that early detection is the key that can transform treatment journeys," he also said.

According to the BBC, Charles maintained an active public schedule, which included numerous overseas trips and royal engagements as part of his official duties, during 2025.

King Charles III became the king of the United Kingdom on Sept. 8, 2022, immediately following the death of his mother, Queen Elizabeth II.

At 73, he was the oldest person to assume the throne. He was formally proclaimed king on Sept. 10 of that year and was crowned on May 6, 2023.

Charles had been the Prince of Wales -- the title reserved for future British kings-in-waiting -- for longer than anyone else in the history of the United Kingdom's monarchy. He has met every American president since Jimmy Carter.

Charles is considered the first modern heir to the British throne. He was sent off to school rather than being tutored privately at Buckingham Palace, and after that he went on to earn a Bachelor of Arts degree at Cambridge.

Charles was later married to Lady Diana Spencer and they had two sons, Princes William and Harry. Lady Diana died in a car crash in Paris on Aug. 31, 1997. He later married Camilla Parker Bowles on April 9, 2005.