Prince Philip, the Duke of Edinburgh, passed away peacefully in his sleep Friday.

His Royal Highness was 99 years old.

Buckingham Palace broke the news in a statement that read in part, “It is with deep sorrow that Her Majesty The Queen has announced the death of her beloved husband, His Royal Highness The Prince Philip, Duke of Edinburgh. His Royal Highness passed away peacefully this morning at Windsor Castle. The Royal Family join with people around the world in mourning his loss.”

Philip will be laid to rest Saturday, April 17, with an eco-friendly send-off that will pay homage to the prince’s environmentalism.

Philip will be laid to rest in a $1,200 wool coffin carried by an electric Land Rover.

Royal insider Omid Scobie revealed that the prince didn’t want an elaborate state funeral and helped plan his funeral in his last days.

“With Prince Philip, he has asked for a much more quieter event. He has asked, in his words, a simple affair and that is exactly what is happening,” he said. “This will really give a chance for the royals to remember his life in a very peaceful and quiet way. It also avoids the worries that the government has over people congregating during the time of the pandemic.”

Philip was originally born in Greece to Prince Andrew of Greece and Denmark, and Princess Alice of Battenberg on June 10, 1921. When he was 18 months old, his family was exiled from the country. He grew up in France, Germany and the United Kingdom, where he joined the Royal Navy in 1939 at the age of 18.

During the Second World War, Philip began writing letters to 13-year-old Princess Elizabeth, whom he had first met in 1934. When he returned from the war he was granted permission by George VI to marry Elizabeth.

Philip was forced to abandon his Greek and Danish titles and styles, and to become a naturalized British subject. He then adopted his maternal grandparents’ surname Mountbatten.

Elizabeth and Phillip were married on November 20, 1947.

Just before the wedding, he was granted the title His Royal Highness and created Duke of Edinburgh, Earl of Merioneth, and Baron Greenwich by the King. Philip left active military service when Elizabeth became queen in 1952, having reached the rank of commander, and was made a British prince in 1957.

He leaves behind his wife of 73 years, Queen Elizabeth II, their four children, eight grandchildren, and 10 great-grandchildren.

The services will take place at St George’s Chapel at Windsor Castle at 3 p.m.

You will be able to watch the service live on CBS.