1. The Eiffel Tower was once yellow.
In fashionable Paris, even the Eiffel Tower must keep up with style trends. Over the decades, the “Iron Lady” has changed her looks with the application of a spectrum of paint colors. When it opened in 1889, the Eiffel Tower sported a reddish-brown color. A decade later, it was coated in yellow paint. The tower was also yellow-brown and chestnut brown before the adoption of the current, specially mixed “Eiffel Tower Brown” in 1968. Every seven years, painters apply 60 tons of paint to the tower to keep her looking young. The tower is painted in three shades, progressively lighter with elevation, in order to augment the structure’s silhouette against the canvas of the Parisian sky.

2. It was built to celebrate the centennial of the French Revolution.
Organizers of the 1889 Exposition Universelle, which commemorated the 100-year anniversary of the fall of the Bastille and the launch of the French Revolution, staged an open competition to design a spectacular centerpiece to their world’s fair. Out of 107 proposals, they selected the design submitted by Eiffel along with architect Stephen Sauvestre and engineers Maurice Koechlin and Emile Nouguier.

3. For four decades it was the world’s tallest structure.
At 986 feet, the Eiffel Tower was nearly double the height of the world’s previous tallest structure—the 555-foot Washington Monument—when it opened in 1889. It would not be surpassed until the completion of the 1,046-foot Chrysler Building in New York in 1930. Although the Eiffel Tower eclipsed the Chrysler Building in height with the addition of an antenna in 1957, it still trailed behind another Gotham skyscraper, the Empire State Building.

4. The Eiffel Tower was once the world’s largest billboard.
When dusk fell across Paris between 1925 and 1936, a quarter-million colored bulbs attached to three sides of the tower’s steeple illuminated to spell the 100-foot vertical letters of the French automobile company Citroën. The advertisement blazed so brightly that it was visible from nearly 20 miles away, and Charles Lindbergh used it as a beacon when he landed in Paris on his 1927 solo trans-Atlantic flight.

5. Eiffel designed part of another famous landmark.
When the initial designer of the Statue of Liberty’s interior elements died suddenly in 1879, French sculptor Frederic-Auguste Bartholdi hired Eiffel as his replacement. Already renowned as a structural engineer and railway bridge designer, Eiffel designed the skeletal support system to which the statue’s copper skin is affixed. (Today, a scale model of the Statue of Liberty stands on an island in the River Seine in the shadow of the Eiffel Tower.)

6. Parisian artists petitioned against the “monstrous” structure.
Although now a worldwide symbol of romance, the radical design of the Eiffel Tower inspired anything but love in the hearts of 300 prominent Parisian artists and intellectuals who signed the following manifesto that ran in the Le Temps newspaper on Valentine’s Day in 1887: “We, writers, painters, sculptors, architects, passionate lovers of the beauty, until now intact, of Paris, hereby protest with all our might, with all our indignation, in the name of French taste gone unrecognized, in the name of French art and history under threat, against the construction, in the very heart of our capital, of the useless and monstrous Eiffel Tower.” The screed even said that the “gigantic black factory chimney” was so loathed that “even commercial-minded America does not want” it.

7. Radio saved the Eiffel Tower from destruction.
Since Eiffel footed 80 percent of the tower’s construction costs, he was permitted to have the structure stand for 20 years in order to recoup his investment before it passed into the hands of the Parisian government, which planned to disassemble it for scrap metal. Seeking a way to prove the structure’s strategic utility in a bid to save it, Eiffel erected an antenna atop the tower and financed experiments with wireless telegraphy that began in 1898. The value of the tower in sending and receiving wireless messages, particularly for the French military, caused the city to renew Eiffel’s concession when it expired in 1909. Today, more than 100 antennae on the tower beam radio and television broadcasts around the world.

An early sketch of the Eiffel Tower

8. The Eiffel Tower contributed to the capture of Mata Hari.
During World War I, the French military used the tower’s wireless station to intercept enemy messages from Berlin. In 1914, the French were able to organize a counter-attack during the Battle of the Marne after secretly learning that the German Army was halting its advance. Three years later, the station atop the Eiffel Tower intercepted a coded message between Germany and Spain that offered details about “Operative H-21.” Based in part on this message, the French arrested, convicted and executed Mata Hari for spying on behalf of Germany.

9. The tower housed a scientific laboratory.
Eiffel engraved the names of 72 of the country’s scientists in the tower’s first-level gallery, and atop the structure he installed a laboratory that was used by himself and French scientists to study astronomy, meteorology, aerodynamics and physiology and test experiments such as Foucault’s Pendulum. In 1909 Eiffel installed an aerodynamic wind tunnel at the base of the tower that carried out thousands of tests, including those on Wright Brothers airplanes and Porsche automobiles.

10. Daredevils have died attempting aerial feats at the tower.
Using everything from parachutes to bungee cords, adventurers for decades have used the tower to stage daring stunts. Not all the thrill-seekers have defied death, however. In 1912, French tailor Franz Reichelt attempted to fly from the tower’s first floor with a spring-loaded parachute suit but crashed 187 feet to the ground instead. Fourteen years later, aviator Leon Collot was killed attempting to fly his plane beneath the span of the tower when it became entangled in the aerial from the wireless station and crashed in a ball of flame.