This illustrated reference takes readers on a revealing tour of a vital, underappreciated piece of our nation's infrastructure. Imagine Washington, D.C., without its clean and effi cient Metro. Or New York City without the Lincoln and Holland tunnels. Or Boston without the Big Dig. This nation without its tunnels would be a quagmire of clogged streets, urban gridlock, massive sewage and water pipes along our sidewalks, and train routes that would take hours longer just to veer around a mountain instead of going straight through it. Unlivable. Tunnels have been built for 200 years to solve some of society's most pressing and dangerous problems. And yet the public rarely understands the complexity of boring through the earth under urban skyscrapers or the danger of burrowing under rivers, lakes, and oceans. This smartly told, beautifully illustrated book, by the construction experts who know the underground world better than anyone, gives tunnels their long-deserved due. This is a story that can only be told by these industry experts who have studied that two-century journey, learned from it, and created the tools and technology needed to improve it. That is what the Underground Construction Association delivers with its beautifully told, richly illustrated book, The History of Tunneling in the United States, which includes a collection of museum-worthy historical photos. The tunneling industry is now big business, and it has a story and a history worth telling.