Courtesy of Pedro Rego Monteiro, Copacabana Beach, Rio de Janeiro.

Under overcast skies, officials and volunteers are busy on Copacabana Beach setting and anchoring of the Olympic 10K Marathon Swim turn buoys, the starting pontoon, the finish chute, the finish touchpad and high-speed cameras, as well as conducting communication checks between officials and safety staff, and going over contingency plans.

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