Since the late nineteenth century, Niagara Falls has been heavily engineered to generate energy behind a flowing façade designed to appeal to tourists. Fixing Niagara Falls reveals the technological feats and cross-border politics that facilitated the transformation of one of the most important natural sites in North America. Daniel Macfarlane details how engineers, bureaucrats, and politicians conspired to manipulate the world’s most famous waterfall. Essentially, they turned this natural wonder into a tap: huge tunnels divert the waters of the Niagara River around the Falls, which ebb and flow according to the tourism calendar. To hide the visual impact of diverting the majority of the water, the United States and Canada cooperated to install massive control works while reshaping and shrinking the Horseshoe Falls. This book offers a unique interdisciplinary perspective on how the Niagara landscape ultimately embodies both the power of technology and the power of nature.