Great wall of Mexico
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There are precedents for President Donald Trump’s plan to build, or complete a 3,208 kilometre wall between Mexico and the US. The Australian outback features not one but two barrier fences, sprawling the length and breadth of the country. A tour guide took us on a sunset tour out to the ‘dog fence’ near Coober Pedy in 2014. The South Australian section of the 5,531km fence which runs from the SA border to Queensland is…