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Since 2003, Henry Gold has led intrepid cyclists on four-month fondos between Cairo and Cape Town. Gold, who previously ran an NGO in Ethiopia, originally conceived Tour D'Afrique as a means to create a business producing cheap mountain bikes in Africa. That part didn't take off, but he did organize the trip on which 33 cyclists set a Guinness World Record for fastest human-powered crossing of Africa. First-time bikers can try to beat it, but it is a hell of a challenge. Four months is basically a sprint across deserts, through jungles, and across savannahs. You've got to be strong to even try it.