Silly letterbox

What is it about the Alstonville Plateau, I wonder? Why is there this fascination with silly letterboxes? Is it the rarified atmosphere at high elevation, all of 140m above sea level? My friend AussieJasmine lives there and has made a study of such things. I'm reluctant to invade her territory, but this one on Houghlahans Creek Road was totally compelling. Its feet are a work of art in themselves - see extra.

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