California Mileage Markers

Calfornia Mileage Marker
©Betsy Malloy Photography

GPS is great if you have an address to navigate to, but sometimes I mention places where there are no nearby major landmarks, no street signs, and no address. It can be hard to keep track of how many miles you've driven from some arbitrary location - and confusing. Fortunately, there's a better way to find things. Those little highway mile markers you may have never noticed beside the road.

To make things easier for you in areas where landmarks and signposts are not available, I often list the nearest highway mileage marker. This is how you read them:

These markers are found on state and county highways, but not on the Interstate or US roads. Look for them at the side of the road, sometimes at the end of a guard rail.

  • The number at the top is the highway number. In the photo, it's CA Hwy 1
  • The letters indicate the county.  For example, this marker is Monterey County (MON) 
  • The numbers indicate the mile it marks. This one is at mile 58,
    • For east-west roads, mile 0 is on the west side, and numbers increase going east. 
    • For north-south routes, mile 0 is at the southern end, and numbers increase going north.
    • Numbering restarts every time you cross a county line.

Reading the sign from top to bottom, it's easy to see that the photographer was standing on California Highway One in Monterey County, 58 miles north of the county line.

Unlike mileage markers in some other states, California markers are numbered in the same sequence going in both directions. If you looked at the marker just opposite this one on the other side of the road, it would be marked the same.

The markers are not at regular intervals and are sometimes extremely close together (or far apart) for no apparent reason - or at least none that I can figure out.

You can also get the same information on bridge signs, where you might see "405 LA 32.46" which means I-405 in Los Angeles County at mile 32.46.

Emergency roadside call boxes also encode the location. Unfortunately, counties are inconsistent about how they do that, and it may take a little thinking to figure it out.