His hands turned the pedals and propelled him up the hill, through soft sandy patches and over rocks and boulders that were seemingly everywhere.

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Puglia's other most inspirational stretch lies between Otranto and Santa Maria de Leuca, interspersing dramatic rocks washed by translucent waters and soft-sand beaches backed by shady forests, where the cri-cri of the cicale (crickets) almost deafens in summer.

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In the following video, you can see one of these soft contraptions as it journeys onto a bed of rocks and then uses colored liquid to blend into its surroundings.

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"The nature of the rocks that we have found, that we think are the ones that contain the clays, are very soft, " explained Prof Squyres.

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