Wrought-iron lattice landmark on the Champ de Mars in Paris…

Wrought-iron lattice landmark on the Champ de Mars in Paris, completed in March 1889 for the World's Fair marking the centenary of the French Revolution. Initially criticised by leading artists and writers as an eyesore, it was saved partly by its usefulness for radio transmission. Now about 330 metres tall, it was the world's tallest man-made structure until 1930, is regularly repainted and welcomes around six million visitors a year.

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