Seattle was paying unusually close attention when Bertha, the world's largest tunnel-boring machine, floated into town this past April.
News choppers hovered and amateur videographers took aim as fire-rescue boats blasted their water cannons to greet the precious cargo. The riggers—who unloaded, moved and set the 7,000-ton TBM's massive parts into an 80-ft-deep launch pit so she could dig the new Alaskan Way Viaduct—were rarely accustomed to such fanfare.