A competitor jumps down a dune on April 5, during the second stage of the 25rd edition of the gruelling 150-mile Marathon des Sables (Marathon of the Sands), nearly 200 miles south of Ouarzazate in Morocco. The race includes a full marathon on one day, a 55-mile stage, as well as others of varying length and terrain during seven days. Competitors must carry all their equipment on their backs. Only a carefully rationed nine liters of water and open-sided local tents are provided daily by the organisers. Over a thousand competitors come from 43 countries, aged 16 to 73.

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