So why are mile markers still relevant when GPS is everywhere?

Surprisingly, none of the major map apps have them. Not Google, Apple, or Waze.

MileCheck is a road intelligence tool that fills that gap. It shows you your exact mile marker, so when something goes wrong, you can give it to dispatch and they can find you.

Here's why that still matters.

1. It's the location format emergency responders actually want

Telling a 911 operator "I'm on I-95" doesn't help much. The interstate runs through a dozen counties and hundreds of miles. A mile marker pins you to a single, spoken, unambiguous point.

This isn't a hunch. State DOTs tell drivers to do exactly this. Virginia DOT puts it plainly: "When calling #77 or 911 for emergency assistance, providing the information on a mile marker sign will help responders reach you quickly." Their own safety patrol crews are dispatched by mile marker.

Source: Virginia DOT, Interstate Mile Markers

2. Your phone's 911 location is often worse than you think

This is the part most people don't know. When you call 911 from a cell phone, the dispatcher usually doesn't get the clean GPS pin you'd see in a rideshare app. They often get a location estimated from the nearest cell tower. The FCC only requires carriers to deliver an accurate location, within about 50 meters, for 80% of wireless 911 calls. Not all of them.

On a highway it gets worse. The towers line up in a row along the road, which is the worst possible geometry for pinpointing you. One Florida 911 coordinator described pings landing "3 houses down from where the caller is actually calling from," and confirmed cross-county misroutes happen "all the time."

So the human still has to say where they are. A mile marker is the fastest, most reliable way to do it.

Sources: FCC Wireless E911 Location Accuracy Requirements · WPTV Investigates, why 911 can't always find you from a cell phone

3. Google Maps and Apple Maps don't show mile markers

Here's the gap that surprises people. The map app you're already staring at won't show you the one number a responder needs. Google Maps and Apple Maps are built for turn-by-turn directions, and they deliberately leave mileposts off the map. There's no setting to turn them on. Google's own support forums just point people to dedicated apps instead.

So even a driver with a full signal and Google Maps open usually can't read off their mile marker. That's the exact gap we built MileCheck to fill.

Sources: Google Maps Community thread · The US Sun, finding mile markers on Google Maps

4. The whole highway runs on mile markers behind the scenes

Mile markers aren't a leftover from before GPS. They're the coordinate system the people who run the roads use every day. Pavement condition, signs, crashes, work zones, maintenance: state transportation agencies locate nearly all of it by route and milepost, using what's called a Linear Referencing System.

It's federal, too. Since 2014 the FHWA has required every state to submit milepost-referenced maps of all public roads for safety and performance analysis. As long as the people managing the highway think in mileposts, the signs on the side of the road have to stay so the two layers line up.

Source: FHWA, ARNOLD / Linear Referenced Data Reference Manual

5. For truckers and breakdowns, the mile marker is the dispatch

Ask any commercial driver. The roadside-assistance script is always the same: name, highway and direction, mile marker, the problem. That's what dispatch uses to route the right tow truck and give an honest ETA.

When it's an 80,000-pound truck on a live shoulder, that one number is the difference between a fast tow and hours of exposure next to traffic. Trucking guidance routinely tells drivers to give both the exact mile marker and the GPS coordinates. They're complementary, not redundant.

Source: TACH, Roadside Breakdown Playbook for Truckers

6. States are still installing more mile markers, on purpose

If mile markers were obsolete, the spending would have stopped. It hasn't. The clearest proof they still matter is that taxpayers keep funding more of them, in the GPS era, because emergency services keep asking.

As reported by Fox News, Oregon DOT spent state safety funds to add markers every half-mile instead of every mile on some routes, because, in their words, "when the only reference on a highway is a mile-long stretch of road, emergency vehicles only guess at the best on-ramp." North Carolina DOT said it has no plans to change how it installs markers despite enhanced 911, because "not everyone owns a GPS and they're not always accurate." A Texas DOT engineer summed it up: "If, for instance, satellites go down, what are we going to do? They're a good backup plan."

Source: Fox News, Your Tax Dollars Are Hitting the (Side of the) Road

So where does that leave you?

GPS is incredible. It's also not the thing that gets a tow truck or an ambulance to you, on a specific stretch of a specific highway, fast. That still comes down to a person reading a mile marker out loud, ideally without squinting for the next little green sign while traffic flies past.

That's the whole reason MileCheck exists. It shows your nearest mile marker in real time, down to a tenth of a mile, and the marker data works even when your signal doesn't, because the moments you most need to know where you are tend to be the moments with no bars. One tap shows your road, your direction, and your exact mile marker, ready to read to a dispatcher or send to whoever's coming to help.

Worth having before you're the one who needs it.