Why are King Charles III and Queen Camilla visiting Washington DC?

King Charles III and Queen Camilla will soon embark on a trip to the United States in what will be the first visit by a British monarch in nearly 10 years.

Among their destinations will be Washington DC, where the king and queen will visit as part of their four-day trip to the US.

Here's what to know about their trip to DC.

When are King Charles III and Queen Camilla coming to Washington DC?

Washington DC will be the first stop in the US for the king and queen. They will arrive April 27 and will join President Donald Trump and first lady Melania Trump at the White House for private tea.

The White House visit will also include a garden party and a ceremonial military review. President Donald Trump is expected to meet with King Charles while their wives have a separate meeting.

On April 28, King Charles will become the second British monarch to address a joint session of Congress.

Speaker of the House Mike Johnson invited the king to address Congress, writing in a letter that lawmakers would be honored to host him.

"We believe an address to Congress will provide a unique opportunity to share your vision for the future of our special relationship and reaffirm our alliance at this pivotal time in history," Johnson said in a letter to the king.

The royals are expected to attended a White House banquet dinner later that night.

Before they leave for New York City, King Charles and Queen Camilla will lay wreath and flowers in a ceremonial tribute to fallen service members.

After New York, they will conclude their U.S. trip at a national park in Virginia, where they will attend a "block party" and watch performances by Appalachian cultural groups. The Virginian-Pilot said it's unclear where in the state the visit will happen.

Why are King Charles III and Queen Camilla coming to Washington DC?

The royals are visiting Washington DC to mark America's 250th anniversary, also called the semiquincentennial.

"Their Majesties’ program will celebrate the historic connections and the modern bilateral relationship between the United Kingdom and the United States, marking the 250th anniversary of American Independence," according to a press release from Buckingham Palace.

The UK Embassy also commented on the importance of the visit.

“The visit will be an opportunity to recognize the shared history of our two nations; the breadth of the economic, security and cultural relationship that has developed since then, and the deep people-to-people connections which unite communities,” the UK Embassy said.