By the 1920s, when Le Corbusier declared that modern architecture had made the mythological Hanging Gardens of Babylon a real possibility in Paris and beyond, roof gardens were already a well-established tradition in many places around the world. From New York to Tokyo, from Mexico City to Marrakesh, people had for many years been ascending homes, theatres, hotels, hospitals, and other buildings to seek sunlight, fresh air, delightful views, and, to greater or lesser extents, the comforting presence of flowers and vines. Aware of the deep antiquity of roof gardens as attested by Roman and Persian historians, roof gardeners of the late 1800s appealed to this history—including the alleged Middle Eastern origin of rooftop life—while also asserting the modernity of elevated green spaces as sites of social reform in industrial cities. The urban poor would particularly benefit from rooftop greenery in crowded, dense neighborhoods, newspaper critics and architectural visionaries claimed, even as real roof gardens frequently served as places of pleasure for the wealthy. Today, as rooftop gardens rise with new speed in global cities like Singapore, Istanbul, and London, it is worth critically analyzing the promises that this globally significant but understudied architectural typology made, kept, and broke a century ago. It may also be valuable to consider how roof gardens can be both radically modern and profoundly ancient at the same time— one might even say that roof gardens are especially modern because they have been so for centuries.
Nathaniel Robert Walker is Professor of Architectural History at the School of Architecture and Allied Arts at the Catholic University of America in Washington, DC. He earned his PhD at Brown University and has published books and essays on the use of architecture as a means of social reform, including dreams and nightmares of the future, such as Architectures of Slavery: Ruins and Reconstructions, Victorian Visions of Suburban Utopia: Abandoning Babylon, and Suffragette City: Women, Politics, and the Built Environment.