He has survived the Cold War, nine American presidents, and innumerable attempts on his life, but as Cuban President Fidel Castro marks his 75th birthday today, many people are wondering what will happen after he dies.
The Cuban leader celebrated deep in the Venezuelan jungle with President Hugo Chavez and Brazil's Fernando Henrique Cardoso.
Chavez, a former revolutionary himself, gave Castro his first army rifle and a statue of South American independence hero Simon Bolivar, Latin American press agencies said.
In Cuba, citizens feted the leader in his absence, cutting cakes, singing songs and holding marches in his honor. "We Cubans wake up happy today," wrote Susana Lee for the ruling Communist Party's daily Granma.
But the leader appears to be showing his age. He stumbled when reporters mobbed him this weekend, and during another part of his trip, he repeatedly complained about the heat.
It's not clear what will happen to Cuba after Castro. But one thing most experts can agree on is that the next president of the island nation will be his younger brother by four years, Raul.
On June 23, the Cuban leader collapsed from heat exhaustion two hours into a speech, raising fears that his end was near.
After the incident, Castro told reporters: "If they tell me tomorrow morning, 'You're having a heart attack,' a sudden death or if I have an accident . . . and I go to sleep for eternity, Raul is the one with most authority and experience."
Raul is head of Cuba's armed forces and No. 2 in the political hierarchy.
Raul has often been described as "pragmatic" — but that doesn't necessarily mean he is reform-oriented, said Dennis Hays, a former State Department official and now a spokesman for the anti-Castro lobby group, the Cuban-American National Foundation.
"He's more ruthless than his brother," said Hays, adding that the pragmatism would only go towards perpetuating the regime.
Antonio Jorge, a professor at Florida International University, agrees with the assessment, but also notes Raul has been widely recognized as a more orthodox Communist than his brother.
"His inner feelings are in favor of a Stalinist regime, [but] he's practical enough to seek accommodation," Jorge said.
Still, that's no reason for optimism. Jorge said others around Raul may be not be as flexible as some of his cadres, and democracy activists might appeal to someone less prominent.
"Can he bring the country to democracy?" Hays asked. "No, absolutely not."
The transition from Fidel to Raul would likely be uneventful, experts said, discounting the likelihood of a military coup or popular uprising upon news of Castro's death.
High-ranking military officials are pretty uniformly loyal to the regime, Jorge said. Anyone with a question mark over their loyalty finds themselves transferred often. A domestic spy network also keeps insurgency at bay.
Jorge noted that most Cubans had little or no access to firearms. There are few civil organizations of any kind, he said, and added that many Cubans were dispirited and pessimistic about their future.
Castro is also treated for his ailments in private, sources say, so the regime would be able to keep a lid on any news of his death until they had a firm grip on security.