What is an Interstate? What is a highway? A turnpike? Is a freeway free?
I was certainly confused by the different types of road in the US, so I did a little researching.
Here is my quick guide (with thanks to far too many websites to mention).
Interstate. This is a country wide system of limited access major roads very similar to the motorway system in the UK. The Interstate system serves nearly all major U.S. cities and comprises about 47,000 miles of major roads. As the name implies, Interstates cross state boundaries.
These are white numbers on a blue background and the numbering system of Interstates is as follows.
US Highway. This is an integrated system of roads and highways numbered within a nationwide grid. North to south highways are odd-numbered, with lowest numbers in the east and highest numbers in the west. Similarly, west to east highways are even-numbered, with the lowest numbers in the north and highest numbers in the south.
US Highway signs are generally black numbers on a white shield shaped background as below.
State Highways. These are the main roads within a state The signs for these are generally black text on a white background in a variety of shapes. Here is one for Florida.
Freeway. Is a general term for a type of road designed for safer high-speed operation of motor vehicles through the elimination of at-grade intersections, with no cross traffic junctions. Such highways are usually divided with at least two lanes in each direction. This can be an interstate, a US highway or a state highway.
Turnpike. This is a toll road.
Don’t Drop The Bike
1 hour ago