Rising 210 metres above the French capital, the Montparnasse Tower has never left anyone indifferent. For many, it remains an anomaly in the Parisian skyline, "a huge block with no expression whatsoever". Over the past five decades, it has even earned nicknames like "the wart", "the eyesore" and "the tombstone". Yet despite its reputation, the edifice continues to draw crowds. More than 30 million visitors have gone to its rooftop terrace to admire sweeping views of the city.