This week we climb what is perhaps the best-known monument in the world: the Eiffel Tower. Completed in March 1889, it ruled supreme as the world’s tallest man-made structure for four decades. During its century-and-a-quarter existence, an estimated 250 million people have been to visit it. But as we will see, the Eiffel Tower wasn’t always universally loved, nor was it intended to still be standing, 127 years after it was built.