context: Colonel Allen Faulkner (Richard Burton), a middled-aged British mercenary and former Army officer, arrives in London from Switzerland to meet the rich and ruthless merchant banker Sir Edward Matherson (Stewart Granger). The latter proposes an operation to rescue Julius Limbani (Winston Ntshona), imprisoned former leader of the fictious central African country of Zembalia, who is due to be killed by the military dictator who overthrew him. Limbani, whose people believe he is already dead, is being held in a remote prison, guarded by ferocious African troops known as the "Simbas", under General Ndofa.Faulkner provisionally accepts the assignment and sets about recruiting his officers, all of whom have worked with him on previous African operations. They comprise:Shaun Fynn (Roger Moore) is a former RAF pilot. He is working as a currency smuggler, but when he realises that he's actually running drugs, he kills the mafia drug dealer and consequently has a death contract placed in his head. Matherson forces the crime boss to lift the contract at the last moment.Pieter Coetzee (Hardy Krüger), is a South African mercenary who only wants to return to his homeland and buy a farm, but can barely afford to pay his rent in London.Rafer Janders (Richard Harris) is hired as an experienced mission planner. He initially refuses the job, as he's making some money as an art dealer and is planning a Christmas vacation with his son, Emile. But Faulkner persuades Janders to join the mission as the tactician.Retired R.S.M (Regimental Sergeant Major) Sandy Young (Jack Watson), is asked by Faulkner to serve as drill sergeant to train the troops and assist in recruitment. He is very willing, but his wife strongly disapproves.With the tacit approval and support of the British government, the 50 soldiers are transported to an unspecified African location, equipped and mercilessly trained by Young. The day before the mission is to begin, Janders exacts a promise from Faulkner to watch over his son Emile, and take care of him should Janders die on the mission. Faulkner agrees.The mercenaries are transported by plane and parachuted into the African country near Zembala Prison. Coetzee uses a powerful crossbow with cyanide-tipped quarrels to take out the prison sentries. The rest of the guards are killed silently with cyanide gas. They rescue Limbani, but he is clearly a sick man and is later hit by crossfire during the battle. The group then makes its way to a small airfield to await pickup.But backers of the project, led by Matherson, reach an agreement with the Zembalese government concerning valuable copper concessions, and the aeroplane due to collect them is recalled at the last minute.The abandoned mercenaries are forced to fight their way through hostile territory, pursued by the Simbas.The relationship between Limbani and Coetzee develops from initial animosity: "I bleed red like you, white man; don't call me kaffir" to one of understanding, as Coetzee comes to understand and appreciate Limbani's struggle, and realises that white and black must work together.Fighting off armed attacks, ambushes and napalm bombing, the mercenaries separate into two groups, and make their way to Limbani's home village, where they intend to provoke a revolution. Faulkner is forced to kill his own men who are gravely injured by an airstrike. Coetzee observes, "we can't leave them to the Simbas", whom will torture him to death.Coetzee is then killed while saving Limbani from a Simba ambush, leaving another soldier to carry Limbani. The medic Arthur Witty (Kenneth Griffith) is killed by machete-armed Simbas while trying to fend off another ambush, allowing the rest of the platoon to escape. Faulkner is reunited with the rest of the remaining 32 mercenaries at Limbani's village where an Irish missionary alerts them to the presence of an aging transport plane, a Douglas C-47 Skytrain aka "Dakota" at an old runway to provide for their escape.As the masses of Simba troops attack, the group attempts to board the plane, but many are killed in the fierce battle. While in the cockpit reading the plane for takeoff, Fynn is shot in the leg, but manages to keep the plane moving. Janders is badly wounded and can't get onto the plane; he implores Faulkner to shoot him as he is running down the runway with mobs of Simba troops in chase. Faulkner cannot bear to shoot his friend, but there is no hope. As Janders cries out his son's name: Emile! Emile!", Faulkner shoots and kills him just as the plane takes off.The plane is initially refused landing permission in nearby Rhodesia, but after they provide proof that Limbani is aboard, they are given permission to land at Kariba. But by the time they land, virtually out of fuel, Limbani has died of his wounds. Flynn passes out, wounded but still alive despite blood loss.Several months later, having managed to return to London, Faulkner breaks into Sir Edward's residence, holds him at gunpoint and takes half of the originally agreed payment from his safe. He then kills him.Faulkner fulfills his promise to Janders. In the closing scene, Faulkner visits Emile at his boarding school. Faulkner offers to tell Emile about his father.
question: Where were the hired soldiers transported to be equipped and physically trained?
answer: An unspecified African location