Royal Library of Belgium

The Royal Library of Belgium anchors the Mont des Arts with a facade of heavy, clean stone lines that hide a vast underground labyrinth. It holds the Dukes of Burgundy’s original collection, a hoard of illuminated manuscripts that barely survived a fire in seventeen thirty-one. While the flames consumed the Coudenberg Palace, soldiers threw chests of books out of windows and into the snow to save them. Today, those fragile pages rest deep beneath the street, far from the light of day.