By 1838, roadbed and trestles had been built north of the city. The original brick roadbed is visible in many places through the asphalt. The Miracle Mile's and Center Boulevard's current "raised roadbed" were the railroad's right of way. Using the slogan "Gravel, the Roadbed to Prosperity", he ran but lost. Note that railroads also have hysteresis in the roadbed structure. Since the parkways used part of the roadbed of Union Turnpike, no houses were demolished. Street-level Mandela Parkway now occupies the previous roadbed of the Cypress structure. The set-up included two parallel strips of concrete that would serve as the roadbed. This is destructive to both the locomotive and the roadbed. When that service was terminated, the freeway was expanded onto the former PE roadbed. In a cable-stayed bridge, the cables run directly between the roadbed and the towers. All of the roadbed and bridges remain in place. Each unit constructed in this fashion creates a single section of bridge, with a roadbed. Between Old Washington and Morristown, the original roadbed has been overlaid by I-70. The vehicle has four-wheel steering atop the surface of a slotted roadbed.