Thanks in no small part to the magazine and TV channel it lends its name to, the Smithsonian Institution has become synonymous the world over with exploration and learning. As the largest museum, research and education complex on Earth – and it's still growing – it looks after sites in Washington DC, New York and Virginia. From its fascinating foundations to its eccentric collections of Americana and arcana, we take a look at the stories and secrets behind the Smithsonian.

Click through this gallery to discover incredible facts about America's richest treasure trove, and how to visit today…

The Smithsonian Institution was established in the name of James Smithson (pictured), a wealthy British scientist who passed away in 1829. In his last will and testament, Smithson stated that if the heir to his fortune – his nephew – should himself die without heirs, then his estate should go "to the United States of America, to found at Washington, under the name of the Smithsonian Institution, an establishment for the increase and diffusion of knowledge". When Smithson’s nephew unexpectedly died in his twenties, the United States government was made aware of this unprecedented bequest.

Congress accepted Smithson’s legacy in 1836, which amounted to more than $500,000 at the time (around £13.1m/$16.9m today). But it was another 10 years before the Smithsonian Institution was finally founded, following a period of sometimes heated debate between educators, politicians, social reformers and civilians. As Smithson’s instructions for what to do with his donation were hazy at best, it could not be decided whether to use the funds for a university, a national library, an observatory or something else. What is now the Smithsonian Institution was ultimately a compromise and culmination of many different ideas.

Despite all of the Smithsonian Institution’s component parts being on American soil, James Smithson had no personal history with the United States, making his gift to the nation something of a mystery. It’s thought by some historians to have been an act of rebellion against the austere attitudes of British society, which had denied Smithson (the illegitimate son of a duke) the right to bear his father’s name. Others believe it was simply him exercising his interest in the Enlightenment principles of democracy and education for all. This blue plaque marks the scientist's former home on Bentinck Street, London.

While he never visited America during his lifetime, James Smithson was eventually acquainted with his beneficiary in 1904 – 75 years after his death. When Smithsonian officials in DC were told Smithson’s gravesite was to be disturbed to make way for a nearby quarry expansion, the decision was made to move his casket from Genoa in Italy to the Smithsonian Institution Building, also known as 'the Castle'. The first of the institution’s sites to be completed, Smithsonian Castle was designated a National Museum in 1858. After travelling for a fortnight by ship, Smithson’s remains were reinterred here and placed in a crypt (pictured), where they have been open to the public ever since​. 

In Washington, this includes: Anacostia Community Museum; Arts and Industries Building; Hirshhorn Museum and Sculpture Garden; National Air and Space Museum; National Museum of African American History and Culture (pictured); National Museum of African Art; National Museum of American History; National Museum of Asian Art's Freer Gallery and Arthur M. Sackler Gallery; National Museum of Natural History; National Museum of the American Indian; National Portrait Gallery; National Postal Museum; Smithsonian American Art Museum; Renwick Gallery; the National Zoological Park; and Smithsonian Castle. There are two venues in New York – the American Indian Museum’s George Gustav Heye Center and Cooper Hewitt, Smithsonian Design Museum – while the Air and Space Museum’s Steven F. Udvar-Hazy Center is in Chantilly, Virginia.

While it is not yet known exactly where in DC they will be located, two new Smithsonian museums are currently in the planning stages after Congress approved them in 2020. The National Museum of the American Latino began showcasing its work with the opening of the Molina Family Latino Gallery (pictured) in June 2022 at the National Museum of American History. This marked the first time a dedicated museum space specialising in the US Latino experience was established on the National Mall. The first digital exhibition for the Smithsonian American Women’s History Museum launched on International Women’s Day 2024, running indefinitely on its website.

Visitors to the National Mall’s Smithsonian buildings will find their museum experience isn’t limited to the indoors. Over 180 acres of manicured gardens, landscapes and grounds wrap around the venues, continuing your education with artistic installations, thought-provoking exhibitions and horticultural displays. Open to all and free to access, this so-called 'museum without walls' features native plants, pollinator gardens, urban bird habitats, calming courtyards and more. Free tours of the Enid A. Haupt Garden (pictured) run every Wednesday morning from May through September. 

The Smithsonian Institution’s entire collection of objects and artworks is estimated to total nearly 157 million pieces (almost 148 million are scientific specimens belonging to the National Museum of Natural History). Only a small percentage of these can be on public view at any one time, with different items coming on and off display every week across its constituent museums. But there are some artefacts that are always kept in the archives, including a macabre hoard of human remains.

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There is a subterranean world lying beneath America’s capital, with around 75,000 square feet (6,968sqm) of concrete corridors and platforms hidden underground. Part of this network is a 700-foot (213m) tunnel running from the Smithsonian Castle (left) to the Natural History Museum (right), dating back to the days when the two sites shared a boiler. It runs right under the National Mall where, during wintertime, snow would melt along the tunnel’s path due to the warm pipes below. The secret passageway helped inspire author Steve Berry’s thriller, The Lost Order.

In the aftermath of the Japanese attack on Pearl Harbor in 1941 (pictured), it was feared that the Axis powers would attempt to strike America again – with Washington and its National Mall deemed prime targets. In order to safeguard the Smithsonian Institution’s irreplaceable items, many of them were moved off the Mall and sent to a clandestine location until 1944. It has since been revealed that over 60 tonnes of its collections were stored in a climate-controlled warehouse near Shenandoah National Park, just outside Luray in Virginia, where guards patrolled 24 hours a day.

From sci-fi and adventure to romance and Disney animation, the Smithsonian museums have received more than their fair share of screen time. The National Air and Space Museum featured in both Transformers: Revenge of the Fallen and Captain America: The Winter Soldier, while scenes of alien aircraft zooming over Smithsonian Castle appeared in two 1950s movies. But the institution’s starring role came in 2009, when several buildings provided the setting for Night at the Museum: Battle of the Smithsonian (pictured). It was also the first time 'Smithsonian' was used in the title of a blockbuster.

This is Cher Ami, one of 600 so-called 'spy pigeons' donated by the British to the US Army Signal Corps’ Pigeon Service of the American Expeditionary Forces (AEF) serving in France. A black check cock homing pigeon, Cher Ami was awarded the Croix de Guerre by the French government for his bravery in carrying life-saving messages during the Second World War. The bird was sadly wounded in action and later died from his injuries. His taxidermied remains are watched over by the National Museum of American History.

Smithsonian’s National Museum of African American History and Culture is the custodian of gold-medal-winning athlete Tommie Smith’s (centre) Team USA warm-up suit from the 1968 Olympic Games. During the medal ceremony for the 200 metres, Smith and his fellow American John Carlos (who won bronze; right) wore these uniforms while giving the Black Power salute on the podium, silently protesting racial inequality. Bowing their heads and raising their black-gloved fists aloft while the US national anthem played, the men also wore black socks with no shoes, representing poverty. The moment gained global attention.

The Smithsonian Institution looks after a number of items that once belonged to past presidents of the United States, from the china cup believed to have held the final drink of William McKinley before his assassination in 1901, to Abraham Lincoln’s beloved top hat (pictured). Last worn in 1865 on the night of Lincoln’s murder at Ford’s Theatre in Washington DC, the silk hat allowed the already-statuesque president (193cm/6’4’’) to stand out even more. The institution also has in its possession a complete set of presidential portraits and even a framed collection of hair clippings from the nation’s first 14 leaders.

Made for the 1939 film production of The Wizard of Oz, these dazzling red pumps were one of as many as 10 pairs designed for Judy Garland’s character Dorothy. The ruby slippers, cared for by the National Museum of American History, are one of just four pairs known to have survived. To protect the famous footwear from deterioration, the Smithsonian needed to build a state-of-the-art preservation case to keep the elements at bay. In 2016 a Kickstarter campaign to fund the project raised over $300,000 (£234,000) from nearly 6,500 pledges. 

President Theodore ‘Teddy’ Roosevelt was a prolific hunter, but even he couldn’t bring himself to shoot an old black bear found tied to a tree in 1902. The media soon turned the story into a satirical cartoon, inspiring Brooklyn store owners Rose and Morris Michtom to start making stuffed bear toys – one of which they called 'Teddy’s Bear', with the approval of the president himself. This sparked a new craze, and one of the Michtoms’ original teddy bears (pictured) was gifted to Roosevelt’s great-grandchildren in the 1960s before joining the Smithsonian collection.

As with tree trunks, whale earwax plugs (like the one pictured here) have layers of light and dark rings that can denote an animal’s approximate age and lifestyle. In some whale species, wax can build up in the ear canal over time and miraculously help amplify a whale’s hearing underwater. Because so much can be gleaned from this unusual substance, the Smithsonian keeps around 1,000 samples of whale earwax in its archives for scientific study, as well as in the Natural History Museum’s Objects of Wonder exhibition.

This gentleman is Hans Langseth, a Norwegian immigrant who lived in North Dakota at the time of his death in 1927. His final wish was to have the impressive facial hair he’d cultivated since the age of 19 cut off and stored for posterity. After decades sat boxed away in an attic, the beard was eventually donated to the Smithsonian Institution. Measuring 17 feet and six inches (533.4cm) long, it is the world’s largest beard, ranging in colour from blonde to dark brunette and showing Langseth’s hair transformation as he aged.

The National Museum of Natural History’s Sant Ocean Hall (pictured) is a monument to the great bodies of water that cover most of our planet – and the incredible creatures that have lurked in them throughout time. It contains more than 600 different specimens, including the terrifying jaws of an extinct megalodon shark and a preserved 25-foot-long (8m) giant squid. Looming over the whole exhibition is Phoenix, the life-sized model of a real North Atlantic right whale who has been tracked by scientists since 1987.

Likely sprung from the Kollur mine in central India, the Hope Diamond weighs over 45 carats and is roughly the size of a walnut. Blueish-purple in colour and set in a necklace of smaller stones, it has been owned by merchants, millionaires and kings in its long life. Stolen from the court of Louis XVI during the French Revolution before finding its way to America, the Hope Diamond was donated to the Smithsonian Institution in 1958 and has since been admired by more than 100 million visitors from all over the world.

Visitors to Smithsonian's National Zoo today will find it in Rock Creek Park, northwest Washington DC. But it actually began with a modest plot on the National Mall, established by William Temple Hornaday. Chief taxidermist at the Smithsonian between 1882 and 1887, Hornaday turned his efforts towards conservation to help combat the near-extinction of America’s wild bison. He later became the Smithsonian’s first head of the Department of Living Animals, bringing bison, badgers, lynx and more to the Mall before the zoo relocated to its present location in 1891.

Named after a fictional bear created to raise awareness of forest fire prevention, the real Smokey Bear was found as a cub among the burnt trees of Capitan, New Mexico, in 1950. Badly injured and unable to return to his forest home, Smokey became a national celebrity and lived out the rest of his life at Smithsonian’s National Zoo, where he received fan mail delivered to his very own zip code. His death in 1976 was widely mourned by adults and children across the country.

When an atomic bomb decimated the Japanese city of Hiroshima in 1945, it was an American B-29 bomber that did the damage. Named the Enola Gay (pictured), the plane was later acquired by the Smithsonian Institution and displayed for the first time in 1994 – but not without some backlash. Ahead of the exhibition, due to criticism from some veterans groups and members of Congress, the curators agreed to omit details deemed to be politically charged and graphic. The plane is now on display at the National Air and Space Museum’s Steven F. Udvar-Hazy Center in Chantilly.

With so many weird and wonderful specimens filling the bowels of the Smithsonian, it’s hardly surprising that some have gone on to make history. In 2016, it was revealed that a new species of river dolphin previously unknown to science had been found on the shelves of the institution’s archives, where its skull had sat for more than half a century. Named Arktocara yakataga, the 25-million-year-old marine mammal is believed to have hailed from the ancient Arctic.

Beyond the biological phenomena, rare gems and quirky curiosities that have come to define the Smithsonian as America’s treasure trove, there are also lesser-told stories of the globe’s diverse communities and cultures to be found in its collection. Founded in 1967, the Anacostia Community Museum (pictured) is dedicated to DC’s Anacostia neighbourhood and “the people [living] furthest from opportunity” in the city. While sharing tales of local African American change-makers and creatives, it also shines a light on issues faced by urban communities all over the world.

From animals and art and heritage and aerospace, the Smithsonian has become America’s – and the world’s – greatest repository of history after nearly 200 years of operation. Travellers to Washington DC can enjoy free admission to all of the capital’s Smithsonian attractions, including the National Zoo, so you’d need to stay in the city for more than two weeks if you wanted to visit a different venue every day. Many exhibitions are also bilingual, notably those at the National Portrait Gallery and the Museum of American History.

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