King Charles has visited a new UK Space Agency observatory and launched a project to track space debris on the final day of his royal visit to Bermuda.

After opening a new coast guard station later in the day, the King donned his sunglasses as he climbed up the boarding steps for his flight home - and bid the British overseas territory farewell.

The King, who arrived in the capital city Hamilton on Thursday, was waved off by dignitaries and a guard of honour formed by the Royal Bermuda Regiment.

It followed his four-day state visit to the US - seen as the biggest diplomatic moment of his reign so far.

The King learned about Project Nova at the observatory on Cooper's Island, which will oversee the installation of a network of telescopes across five sites to help track material in space, such as old satellites and rocket stages.

He then opened a new Great Bay Coast Guard Station in St David's, where he awarded operational medals to members of the Royal Bermuda Regiment and viewed new technology used to protect the island's waters and marine environment.

Later at LF Wade International Airport, a small group of dignitaries including Premier David Burt gathered as the King drew the visit to a close.

The monarch walked a short stretch of red carpet and spoke to leading figures including the commissioner of police Darrin Simons and leader of the opposition Ben Smith.

Shortly before boarding the plane, the King posed for a photo with assembled officials including police and security personnel.

It followed the first full day of his visit on Friday, which included a boat trip with the coastguard, a cake-cutting event and a visit to the National Museum of Bermuda.

He also viewed artefacts from the transatlantic slave trade and visited a conservation initiative.

The trip marked King Charles's first visit to a British overseas territory since taking the throne.

"I am told to my amazement it is also the first time in Bermuda's 400-year history that the islands have received a reigning King," he told guests at a garden party on Friday evening. "I am terribly sorry it has taken so long."

"I need hardly say that Bermuda, like all the overseas territories, is a most cherished and important member of the British family," the King said during the gathering at Government House.

He had received a ceremonial welcome earlier in the day in the former capital of St George, where his arrival was marked with a 21-gun salute and a military procession - and, later, a marching band playing a rendition of Jamming by Bob Marley and the Wailers.

He landed in Bermuda after departing the US state of Virginia on Thursday, where he and Queen Camilla concluded their state visit by meeting members of the public at a community parade in small-town America.

It followed days of formalities and diplomatic challenges in Washington DC, in which they were welcomed to the White House by US President Donald Trump and the King delivered a historic address to both houses of the US Congress.

They also visited New York City, where their engagements included laying flowers at the September 11 Memorial and meeting families of those who lost their lives in the 2001 attacks.

Part of the State Opening of Parliament, the King's speech sets out the government's political agenda.

The US president said he would lift restrictions on Scotland's ability to work with the state of Kentucky on whisky and bourbon.

King Charles III and Queen Camilla are concluding their four-day state visit to the US, bidding farewell to President Trump and First Lady Melania Trump.

King Charles' historic state visit, the first by a British monarch since Queen Elizabeth II's in 2007, has come to an end.

BBC's Sarah Smith looks at whether King Charles' charm offensive with President Trump made a difference to US-UK relations.