My name is Don Milne and I'll be your travel guide on this virtual tour of the U. S. of A. First, I suppose you're wondering why ROADTRIP-'62 TM is different from other travel sites? There's a very simple answer: everybody else travels only in space, but we also travel in time! That's right, we don't just go somewhere, we also go somewhen. We will drive on highways as they were in 1962, try to eat only at restaurants that existed in 1962, try to stay only at motels that existed in 1962, try to buy gas and sundries, play the music, see only the sites across America, and just generally live in America as it was in 1962!
Of course we'll need a time machine, and ours is this beauty of a car! It's a 1962 Chevrolet Impala, lovingly restored to look and run like new. Now, let's see where we'll be going! We're going to drive the US-numbered routes of 1962. Because we'll be using the roads of 1962, that means we won't be on freeways very much. There weren't many freeways in 1962, as the country had just begun building the Interstate system, so we'll travel mostly the two-lanes through every little town on the way.
I'm going to begin this discussion on bridges with the big one we saw two days ago: the Mackinac Bridge. It was only completed in 1957 and so was still pretty new in 1962. Today, it carries I-75 over the Straits of Mackinac, but originally the bridge was signed as US-27. Because we keep building bigger and longer, it's now only the third longest suspension bridge in the world, but it was the longest from 1957 to 1998.
The idea for a bridge at this point dates back to 1884, because it was realized that year-round ferry service across the Straits of Mackinac was a failure. Therefore, if a true east-west transcontinental route for either rail or road traffic were to be established through Michigan, a bridge or tunnel would have to be constructed. TheBrooklyn Bridge in New York had been opened in 1883, so the concept of a suspension bridge of great length was proven. Within a few years, railroad companies began to view the idea with real interest, with Cornelius Vanderbilt of the New York Central Railroad noting that the Grand Hotel on Mackinac Island was one of the best hotels if its kind in the world, but suffered from a short business season. He felt a bridge would be helpful. Also, in 1889, construction began on the Firth of Forth Bridge in Scotland.
In the 1920s, many ideas were proposed to connect Michigan's two peninsulas besides the suspension bridge. These included a floating tunnel, and a series of bridges connecting various islands in the area, presumably to avoid the most dangerous crossing of the Straits. This first study found that a bridge was feasible and estimated the cost at 30 million dollars. By 1934, the bridge was proposed as a suitable federal Public Works Administration (PWA) project. The Michigan Legislature created the Mackinac Straits Bridge Authority to further study the feasibility of a bridge, and to finance the work by revenue bonds. The Mackinac Straits Bridge Authority was temporarily abandoned between 1947 and 1951, but the problem of connecting the peninsulas forced it to be recreated. When the bridge opened on November 1, 1957, it was on schedule, despite the hazards construction within the Straits of Mackinac. In fact, construction was so dangerous that five men died during the project.
As noted, suspension bridges have been used to span long distances for over a century. But this is only for modern, steel-cabled structures. The first design for a bridge that resembled modern suspension bridges in Europe is attributed to Faust Vrančić. James Finley constructed an iron chain bridge at Jacob's Creek, Pennsylvania, in 1801, becoming the first of this design. This bridge attained wide notoriety and from about 1810 a rapid period of development of the modern suspension bridge occurred.
The modern descendent of a beam bridge is the pre-stressed concrete beam bridge. In this, beams are constructed of concrete with steel reinforcing, and the various length beams are set across piers. Most modern freeway bridges and many river bridges along US-23 are of this type, as it is relatively inexpensive and quick to erect.
The next more complicated type of bridge is an arch bridge, developed to a high degree by the Romans. In this type, longer spans are possible than for a beam because the weight is distributed around and down the arch, instead of depending on the strength of the beam. An example of a concrete arch on US-23 is the Scott Creek Bridge in Sylva, North Carolina. These bridges are usually over rather smaller rivers.
One type of bridge erected often during the 1800s is the truss bridge. This is really a variation on a beam, with the solid beam replaced by a latticework of wood, iron or steel trusses to distribute the weight. In effect, the beam has been hollowed out and you drive through the middle! The defining feature of a truss bridge is the repeated triangular shapes, used because a triangle cannot be distorted by stress. There are several places along US-23 where a slight detour will take you to some remaining covered bridges, such as near Upper Sandusky, Ohio and Graysbranch, Kentucky.
There are also several designs of moveable bridges. We usually call these all drawbridges, but the several types are more properly vertical lift bridges, swing bridges, rolling lift bridges, and bascule bridges. One moderately famous bascule bridge was located on US-23/I-75 at Zilwaukee, Michigan. The Zilwaukee Bridge was a two span drawbridge, constructed in 1960. The reason it was famous is that it was one of very few drawbridges constructed on an Interstate freeway. The idea of the Interstates was that there would be no stops or traffic signals, but a drawbridge required both whenever a ship crossed. Besides the normal traffic backups whenever the bridge opened, the river channel under the bridge was narrow and several ships actually hit the bridge over the years. This caused damage and additional backups on the freeway. It continued to obstruct both highway and river traffic until 1988, when a high-level bridge was opened that went above the shipping channel on the Saginaw River.
One other beautiful bridge that was on US-23 back in 1962, but that the highway has bypassed since, is the Anthony Wayne Bridge over the Maumee River in Toledo, Ohio. This is another suspension bridge, with a center span of 785 feet. It was constructed in 1931, rehabilitated in 1961 and again in 1998, when 240 suspender cables and anchorage cables were replaced and the main cables were re-wrapped. The latticework of the towers and decorative sidewalk railings help create a very pleasing view. Currently, OH-2 crosses the bridge: I have not been able to find the date when US-23 was moved, though it may have used the nearby Cherry Street Bridge for some period.