The Transcontinental Railroad, laid across the United States during the 1860s, remains the very epitome of contradiction. On the one hand, it was a triumph of engineering skills over thousands of miles of rough terrain, but on the other hand, it drained the natural resources in those places nearly dry. It “civilized” the American West by making it easier for women and children to travel there, but it dispossessed Native American civilizations that had lived there for generations. It made the careers of many men and destroyed the lives from many others. It was bold and careless, ingenious and cruel, gentle and violent, and it enriched some and bankrupted others. In short, it was the best and worst of 19th century America in action.

Traveling around the tip of South America was fraught with danger, and European explorers and settlers had proposed building a canal in Panama or Nicaragua several centuries before the Panama Canal was actually built. Taking about 10 years to build, workers had to excavate millions of cubic yards of earth and fight off hordes of insects to make Roosevelt’s vision a reality. Roosevelt also had to tie up the U.S. Navy in a revolt in Colombia to ensure Panama could become independent and thus ensure America had control of the canal.

During the 1930s, at the height of the Great Depression, thousands of workers began work on the Hoover Dam, built in the Black Canyon, which had been cut by the powerful Colorado River. The Colorado River was responsible for the Grand Canyon, and by the 20th century, the idea of damming the river and creating an artificial lake was being explored for all of its potential, including hydroelectric power and irrigation. By the time the project was proposed in the 1920s, the contractors vowing to build it were facing the challenge of building the largest dam the world had ever known. As if that wasn’t enough, the landscape was completely unforgiving.