The Western Railroad, which passes through the Berkshires of Massachusetts, radically changed the world when it opened in 1841. At 1,459 feet above sea level, it was the highest and longest railway ever built. The Western Railroad moved railroads from a novelty to the forefront of modern transportation. And reminders of that industrial age can be found today, deep in the woods of the Hilltowns, along the Keystone Arch Bridge Trail.