06/17/2026
A friend of the Institute headed into the Indian Peaks Wilderness, managed by the U.S. Forest Service and the National Park Service, in Colorado for his first solo backpacking trip.
Four days. 30 miles. 3,800+ feet of elevation gain. No cell service for much of it.
We suggested he load USNGapp.org on his phone, a progressive web app that works even without cell service, and pair it with the U.S. Geological Survey (USGS) 1:24,000-scale topographic map for the area. He also carried a Romer grid reader, a small transparent plastic card with markings that correspond directly to the scale of the map he was using.
Here's why that combination matters: the red grid printed on a USGS map and the coordinate displayed on USNGapp.org speak the same language. When his app showed 13T DE 4673 3591, he could place that coordinate on his paper map using his Romer grid reader and know precisely where he stood, relative to the trail, the ridge, the lake, the way out.
The point isn't that something went wrong. It's that he was prepared if it did.
For trail builders inclined to go a step further, USNG coordinates can also appear on physical printed signs called Emergency Location Markers (ELMs), giving trail users and rescuers a shared language of location right there on the ground.
Fifteen minutes learning about U.S. National Grid might be the most valuable thing you do before your next backcountry trip.
