They are mostly found on sandstone and the decoration is usually of cup-like features or complex patterns of cups, rings and grooves.

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"First, the organization of a World Cup, which is the biggest challenge in terms of country-wide organization. (The World Cup) today is a very complex event to organize, " he says.

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What makes any potential tie-up all the more complex is that any stadium involved in the World Cup comes under the control of the International Rugby Board.

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Last year the Hainan Island development staged the World Cup teams event for the first time, taking over from the Mission Hills complex at Shenzhen.

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