Your exact position on the route, counted in miles from the state line or the highway’s southern or western start. Exit numbers usually match these miles.
Notice them occasionally. In a breakdown or emergency, the nearest mile marker is how you tell responders exactly where you are.
The road’s page numbers. "I-80, mile 124, westbound" finds you faster than any description of trees.
Calling for help with no idea of location. One glance at the last marker turns "somewhere on the highway" into a pinpoint.
Signs that live in the same family, or get confused with this one.
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