Built in France’s Loire Valley from 1519 to 1547, the Chateau de Chambord was a hunting lodge for King Francis I, who already had palaces at Blois and Amboise and wanted to impress his rival, Holy Roman Emperor Charles V. It has 440 rooms, 84 staircases, 282 fireplaces, and a moat and bastions useless against attack. Francis spent only about seven weeks there. His entourage of up to 2,000 people had to haul in every barrel of wine and sack of grain, and the unfurnished shell required modular furniture carted in for each visit. By his death it had cost 444,070 livres. The design is credited to Domenico da Cortona, but Leonardo da Vinci, living near Amboise as the king’s guest, is widely thought to have shaped it.

After Francis died, the court abandoned the drafty building for 80 years until Gaston, brother of Louis XIII, restored it in 1639. Louis XIV added a stable for 1,200 horses and Moliere premiered Le Bourgeois Gentilhomme there. Later residents included the deposed Polish king Stanislaw I and Marshal Maurice de Saxe with his regiment. In 1792 revolutionaries sold the furnishings and ripped up the floors, and auctioneers burned carved doors to stay warm. It served as a field hospital in the Franco-Prussian War, was seized as enemy property in World War I, and in 1939 hid thousands of works from the Louvre along with Jewish children protected by the Resistance.

• The double helix staircase where two people can climb three floors at once and never meet
• An abandoned pinwheel foundation found beneath the chateau, echoing da Vinci’s turbine and rotor sketches
• A roofline of 11 kinds of towers and three types of chimneys meant to evoke Constantinople’s skyline
• A B-24 Liberator bomber crashing on the chateau lawn in June 1944
• The 2016 flood of the Cosson that made the chateau rise from water, as Francis dreamed after reading Amadis de Gaula