On Monday two simultaneous 21-gun salutes will fire in Havana and Santiago de Cuba to pay tribute to Castro, who ruled Cuba for nearly five decades, according to Cuba's state news agency.
On Tuesday evening in Havana, at least tens of thousands are expected to pay tribute to Castro in the large plaza named for national hero Jose Marti, a poet and leader of Cuba's 19th century fight for independence from Spain.
On Wednesday Castro's ashes will begin a ceremonial journey east across the country, the reverse of the route Castro and his band of rebels took to seize power from dictator Fulgencio Batista in 1959.
His ashes are expected to arrive in Santiago de Cuba Saturday for a 7 p.m. rally at the Antonio Maceo Revolution Square
On Tuesday through Saturday there will be cannon firings every hour on the hour from 6 a.m. to 6 p.m.
And on Sunday, Castro's ashes will be interred in the same cemetery where Marti is buried after a 7 a.m. service. At 9 a.m. that day, another 21-gun salute will fire simultaneously in Havana and Santiago de Cuba.
Sadness and joy
Castro died Friday at 90
. His brother, Raul Castro, announced his death in a televised statement Saturday.
"I say to the people of Cuba, with profound pain I come here to inform our people, our friends of America and the world, that today, 25 November, 2016, at 10:29 pm, died the chief commander of the Cuban revolution, Fidel Castro Ruz," Raul Castro said.
A concert by famed tenor Placido Domingo was canceled and clubs usually alive with music went silent as public performances were stopped.
Cuban radio and television will broadcast patriotic and historical programming during the nine days of mourning that began Saturday, state news outlet Granma reported.
"The Cuban people are feeling sad because of the loss of our commander in chief Fidel Castro Ruz, and we wish him, wherever he is, that he is blessed, and us Cubans love him," a young Cuban woman told CNN.
At the University of Havana, where Castro attended law school 70 years ago, people placed flowers and photos by a statue on the campus' main steps.
In Bíran, a town near Cuba's eastern tip where Castro was born, people flocked to the home of his half-brother, Martin Castro. They wanted to know whether the hometown revolutionary was dead.
"They have been knocking and calling and asking if it is true," said Angel Daniel Castro, a nephew of Fidel Castro's.
"For us, he was like a father. And Cuba sees him as a father. One woman just called crying and saying she had lost her father. Everyone feels it."
In Florida, however, the mood was decidedly more festive. Revelers spilled into the streets of Miami
's Little Havana neighborhood early Saturday. They popped champagne, clanged pots, cheered and waved the Cuban flag with signs reading, "Satan, Fidel is now yours."
"It means a lot for us Cubans," a reveler told CNN affiliate WSVN. "It's a moment that we've been waiting for 55 years....The man that caused so much suffering ... has passed away."
Johandys Comas, a 41-year-old Cuban in Miami who left his home country in 2004, described the mood as sober in his Cuban hometown of Cienfuegos.
"It's a party here, but back home my dad says it's quiet and everyone's mostly staying inside," Comas said. "You can't speak out in Cuba."
Castro's long reign
Castro reigned with an iron hand for nearly five decades, defying a US economic embargo intended to dislodge him. He remained committed to keeping Cuba a one-party, communist state after the fall of the Soviet Union, his chief sponsor during the years of mutual antagonism with the United States.
At the height of the Cold War, Castro used a blend of charisma and repression to install the first and only communist government in the Western Hemisphere, less than 100 miles from the United States.
Repressive laws allow the government to jail and punish its critics, such as dissidents and journalists, with long prison sentences, according to Human Rights Watch.
"There are few individuals in the 20th century who had a more profound impact on a single country than Fidel Castro had in Cuba," Robert Pastor, a former national security adviser for President Jimmy Carter in the 1970s, told CNN in 2012.
"He reshaped Cuba in his image, for both bad and good," said Pastor, who died in 2014.
Although Castro's stage was a small island nation
, historians say he commanded worldwide attention.
"He was a historic figure way out of proportion to the national base in which he operated," said Louis A. Perez Jr., author of 10 books on the Caribbean island and its history.
Castro, known universally as "Fidel," held on to power for 47 years until illness forced him to relinquish his duties to younger brother Raul in July 2006. Castro resigned as president in February 2008, and Raul took over permanently.
But Fidel Castro lived long enough to see a historic thaw between Cuba and the United States. The two nations reestablished diplomatic relations in July, and President Barack Obama visited the island this year.
Obama extended "a hand of friendship to the Cuban people" as he offered his condolences to the Castro family.
"We know that this moment fills Cubans -- in Cuba and in the United States -- with powerful emotions, recalling the countless ways in which Fidel Castro altered the course of individual lives, families, and of the Cuban nation," he said.
"History will record and judge the enormous impact of this singular figure on the people and world around him."
Other world leaders react
Chinese President Xi Jinping hailed Castro as a "great leader" for the Cuban people and said China had lost "an intimate and sincere friend," according to a statement read on Chinese state TV.
"He achieved immortal historical achievements for the development of world socialism. He was the great person of our era, and people and history will remember him," Xi said. "Great Castro will live forever. "
Mexican President Enrique Peña Nieto called Castro a friend of Mexico who had promoted bilateral relationships based on "respect, dialogue and solidarity."
Canadian Prime Minister Justin Trudeau described Castro as "a larger-than-life leader
who served his people for almost half a century. A legendary revolutionary and orator, Mr. Castro made significant improvements to the education and health care of his island nation."
Other leaders noted Castro's global impact but declined to praise a man who was criticized for his record on human rights.
French President François Hollande said Castro "embodied the Cuban revolution, with the hopes it aroused and then in the disillusion it provoked."