There’s an invisible network connecting every corner of the United States. Without it, cars wouldn’t start and lights wouldn’t turn on. At 2.6 million miles, if it were stretched out, it would reach around the Earth more than a hundred times. Chances are, you’ve never noticed it. The nation’s sprawling pipeline network is buried underground, out of sight and out of mind. But it wasn’t always the case that pipelines crisscrossed the nation, bringing energy where it was needed.