The History of Rapid Transit

The first city to electrify their L entirely was of all places Sioux City, Iowa. These were almost all privately built and loud because wooden ties directly on steel girders does not dampen vibrations very well. The train would come every 90 or even every 60 seconds - something we can't do anymore. It's harder to do line of sight and tunnels is the thing. This was also a dangerous system. And this was before the invention of the great American tradition of stealing rides on trains.