They call it the nation's attic: the Smithsonian Institution, founded in 1846, comprises 19 museums, most of which are found in Washington, DC. Inside, you’ll find roughly 156 million pieces in total, each one connected to the American experience. With so many one-of-a-kind items on display, where to begin? If you don't have a week to rummage through the attic, start with our guide to the top 10 treasures on the National Mall.

The Star-Spangled Banner
Where to find it: Star-Spangled Banner Gallery, National Museum of American History
During the War of 1812, George Armistead, the commander of Fort McHenry in Baltimore Harbor, demanded 'a flag so large that the British would have no difficulty seeing it from a distance.' Local flagmaker Mary Young Pickersgill took up the challenge, sewing a monstrous Stars and Stripes measuring 30 x 42 feet. Each of the 15 stripes span 2ft and each star is 2ft in diameter. Hoisted above the fort on a 90ft flagpole, this very flag was spotted on the morning of September 13, 1814, by attorney and amateur poet Francis Scott Key, after enduring 25 hours of bombing. And it was this very flag that inspired Key to scribble the poem 'Defense of Fort McHenry'. His little ditty was set to music, eventually becoming 'The Star-Spangled Banner,' which was declared the national anthem of the United States in 1931.
Lincoln’s top hat
Where to find it: American Presidency exhibition, 3 Center, National Museum of American History
Abraham Lincoln loved wearing high top hats. This one was made by JY Davis in Washington, DC, and had the black silk mourning band added in remembrance of his son Willie. The last time the president wore this hat was the fateful evening of April 14, 1865, when he attended the play Our American Cousin at Ford’s Theatre and was shot by John Wilkes Booth. While Lincoln was carried across the street to the home of William Petersen, where he would die the next morning, the hat remained in the presidential box. The War Department recovered the hat and, with permission from Mary Lincoln, gave it to the Patent Office; it was transferred to the Smithsonian in 1867.

Charles Lindbergh’s Spirit of St Louis
Where to find it: Boeing Milestones of Flight Hall, National Air and Space Museum
Determined to win the $25,000 prize offered to fly the risky, physically demanding, nonstop solo journey between New York City and Paris, Charles Lindbergh modified a Ryan M-2 with increased wingspan and longer fuselage; he also pushed back the cockpit and moved the engine forward. On May 20, 1927, with the world holding its breath, Lindbergh set out from NYC on a 33-hour and 30-minute flight that took him 3,610 miles across the Atlantic. Landing at Le Bourget Field and greeted by a fervent crowd, Lindbergh became not only the first solo transatlantic pilot but also an international hero. (Needless to say, he won the prize.) Following an international victory tour, the Spirit made its final flight to the Smithsonian Institution on April 30, 1928.

Louis Armstrong's brass trumpet
Where to find it: Musical Crossroads exhibition, Culture Galleries (L4), National Museum of African American History and Culture
Legendary jazz musician Louis Armstrong moved listeners with soul-baring, improvised trumpet solos showcased in such heart-rending songs as 'It’s a Wonderful World' and 'A Kiss to Build a Dream On.' As Armstrong himself once stated: 'When I pick up that horn, that’s all. The world's behind me, and I don't concentrate on nothing but that horn.' He went through many trumpets over the years, but this one – a custom, personally inscribed, Selmer B♭ brass trumpet – was by his side for five decades.
Julia Child’s Kitchen
Where to find it: FOOD: Transforming the American Experience exhibition, 1 East, National Museum of American History
Julia Child gave lessons, tested recipes and cooked in her custom-built Cambridge kitchen, which was made famous as the filming site for many of her TV shows, including The French Chef. In 2001, some 1,200 items from the kitchen were packed and reassembled in the museum – cookbooks, copper pans, the aquamarine cabinets, the six-burner commercial Garland range, and yes, the kitchen sink.

The Peacock Room
Where to find it: Freer-Sackler Museums of Asian Art
Detroit industrialist Charles Lang Freer was good friends with artist James McNeill Whistler, which explains why Freer Gallery, the National Mall’s oldest Smithsonian museum and predominantly a showcase of Asian art, contains many paintings by Whistler and his contemporaries. It also explains how the gorgeous but seemingly incongruous Peacock Room ended up here. It all started in 1876, when British shipping magnate Frederick Leyland commissioned Thomas Jeckyll to design a dining room to showcase his Chinese porcelain; Jeckyll in turn consulted Whistler. While Jeckyll took sick leave, Whistler went crazy with his vision of the room, adding ornate details, including peacocks on the shutters. The artist charged Leyland some $200,000 extra for what he described as 'a gorgeous surprise.' Leyland was surprised all right – and refused to pay the extra fee. Freer bought the room intact from a London dealer in 1904 and installed it in his Detroit house. He bequeathed it to the Smithsonian with the rest of his Whistler collection, and it was moved to Washington in 1919.
The Hope Diamond
Where to find it: Earth Sciences wing, 2nd floor, National Museum of Natural History
Diamonds are often referred to as a girl’s best friend, but in the case of the dazzling, deep blue, 45.52-carat Hope Diamond, the gemstone is better described as a troublemaker. Jean-Baptiste Tavernier, the noted 17th-century French traveler, came across the bauble on his explorations of India. Legend dictates it had been stolen from a temple where it was protected by a curse. Future owners included Louis XIV (who died of gangrene and had only one child survive to adulthood), Marie-Antoinette (we know what happened to her), Evalyn Walsh McLean (whose mother-in-law, son and daughter died and whose husband left her for another woman) and Harry Winston, who donated it to the Smithsonian in 1958. Winston got off easy, but the mailman who delivered the stone to the Smithsonian suffered a broken leg in a truck accident, a head injury in a different accident, lost his wife and his dog, and saw his house burn down.

Marian Anderson’s silk ensemble
Where to find it: Musical Crossroads exhibition, Culture Galleries (L4), National Museum of African American History and Culture
World-famous singer Marian Anderson wore this orange shantung silk blouse and flowing black silk velvet skirt while giving a landmark concert on the steps of the Lincoln Memorial in April of 1939. Though she had enchanted audiences around the globe throughout the 1930s, in segregated Washington, DC, Anderson was not allowed to book an integrated show at Constitution Hall. First Lady Eleanor Roosevelt intervened, and, with FDR, arranged to have Anderson perform at the Lincoln Memorial instead. More than 75,000 people showed up for that Easter Sunday concert. Secretary of the Interior Harold Ickes introduced her, stating: 'In this great auditorium under the sky, all of us are free.' Anderson opened with 'America' and closed with 'Nobody Knows the Trouble I’ve Seen'.

Moon Rock
Where to find it: Milestones of Flight gallery, National Air and Space Museum
It’s unfathomable, really, the fact that you’re touching a piece of the moon. But this 3.8-billion-year-old specimen of basalt was collected on the Apollo 17 mission in December 1972 on the edge of the Sea of Serenity. It’s one of the National Air and Space Museum’s most popular exhibits, displayed near the Lunar Module LM-2 that was used to ferry two astronauts from the lunar orbit to the lunar surface and back.
Ernie and Bert (and Rubber Duckie)
Where to find them: “American Stories” exhibition, 2 East, National Museum of American History
Oodles of preschoolers learned about friendship from this dynamic duo. Part of the endearing crew of Muppets created by puppeteer Jim Henson, Ernie and Bert first appeared in 1969 on the educational TV series Sesame Street, where Ernie performed his beloved 'Rubber Duckie' song. The Muppets went on to star in several movies and TV specials. Henson’s daughter Cheryl Henson donated Ernie and Bert, as well as 19 other Muppets and props, to the Smithsonian in 2013.

Bonus item: Dorothy’s ruby slippers
Dorothy Gale, played by a 16-year-old Judy Garland, wore these iconic shoes in the 1939 MGM movie The Wizard of Oz. There were actually several pairs made for the film – five are known to have survived. In the original children’s book, The Wonderful Wizard of Oz, by L Frank Baum, Dorothy’s shoes were silver; the color was changed to take advantage of the new Technicolor film process. The slippers are currently being repointed, but you can find them in the American Stories exhibition, 2 East at the National Museum of American History once they return to display in mid-2018.
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